Reduction in necrotizing enterocolitis and improved outcomes in preterm infants following routine supplementation with Lactobacillus GG in combination with bovine lactoferrin

Analysis of Bifidobacterium animalis subsp. lactis BB-12 ® and Lactobacillus rhamnosus GG on underweight and malabsorption in premature infants

OBJECTIVE

This study aimed to explore and analyze the therapeutic effect of the combination of Bifidobacterium animalis subsp. lactis BB-12® and Lactobacillus rhamnosus GG on underweight and malabsorption in premature infants.

METHODS

This is a retrospective study. The clinical data of 68 premature infants admitted to Beijing United Family Hospital (Private Secondary Comprehensive Hospital, Chaoyang District, Beijing, China) from January 2016 to January 2022 were analyzed retrospectively. Preterm infants less than 37 weeks of gestational age admitted to the neonatal intensive care unit were included in the study. Patients with intestinal malformations, necrotizing enterocolitis, etc., who require long-term fasting were excluded. A telephone follow-up was performed 3-6 months after discharge. They were classified as treatment groups A and B according to the treatment plan. The treatment group A included parenteral nutrition, enteral nutrition, etc. In treatment group B, based on treatment group A, the premature infants were treated with Bifidobacterium animalis subsp. lactis BB-12® and Lactobacillus rhamnosus GG. The time to regain birthweight and the weight on day 30 were compared between the two groups, as was the duration of transition from parenteral nutrition to total enteral nutrition.

RESULTS

The time of weight regain birthweight in group B was shorter than that in group A (t=-2.560; t=-4.287; p<0.05). The increase of weight on day 30 in group B was significantly higher than that in group A (t=2.591; t=2.651; p<0.05). The time from parenteral nutrition to total enteral nutrition in group B was shorter than that in group A (z=-2.145; z=-2.236; p<0.05).

CONCLUSION

In the treatment of premature infants, the combination of Bifidobacterium animalis subsp. lactis BB-12® and Lactobacillus rhamnosus GG can have a better therapeutic effect on the underweight and malabsorption of premature infants, and this treatment method can be popularized in clinics.

The Detrimental Effects of Peripartum Antibiotics on Gut Proliferation and Formula Feeding Injury in Neonatal Mice Are Alleviated with Lactobacillus rhamnosus GG

Peripartum antibiotics can negatively impact the developing gut microbiome and are associated with necrotizing enterocolitis (NEC). The mechanisms by which peripartum antibiotics increase the risk of NEC and strategies that can help mitigate this risk remain poorly understood. In this study, we determined mechanisms by which peripartum antibiotics increase neonatal gut injury and evaluated whether probiotics protect against gut injury potentiated by peripartum antibiotics. To accomplish this objective, we administered broad-spectrum antibiotics or sterile water to pregnant C57BL6 mice and induced neonatal gut injury to their pups with formula feeding. We found that pups exposed to antibiotics had reduced villus height, crypt depth, and intestinal olfactomedin 4 and proliferating cell nuclear antigen compared to the controls, indicating that peripartum antibiotics impaired intestinal proliferation. When formula feeding was used to induce NEC-like injury, more severe intestinal injury and apoptosis were observed in the pups exposed to antibiotics compared to the controls. Supplementation with the probiotic Lactobacillus rhamnosus GG (LGG) reduced the severity of formula-induced gut injury potentiated by antibiotics. Increased intestinal proliferating cell nuclear antigen and activation of the Gpr81-Wnt pathway were noted in the pups supplemented with LGG, suggesting partial restoration of intestinal proliferation by probiotics. We conclude that peripartum antibiotics potentiate neonatal gut injury by inhibiting intestinal proliferation. LGG supplementation decreases gut injury by activating the Gpr81-Wnt pathway and restoring intestinal proliferation impaired by peripartum antibiotics. Our results suggest that postnatal probiotics may be effective in mitigating the increased risk of NEC associated with peripartum antibiotic exposure in preterm infants.

Necrotizing enterocolitis: recent advances in treatment with translational potential

Necrotizing enterocolitis (NEC) is one of the most prevalent and devastating gastrointestinal disorders in neonates. Despite advances in neonatal care, the incidence and mortality due to NEC remain high, highlighting the need to devise novel treatments for this disease. There have been a number of recent advancements in therapeutic approaches for the treatment of NEC; these involve remote ischemic conditioning (RIC), stem cell therapy, breast milk components (human milk oligosaccharides, exosomes, lactoferrin), fecal microbiota transplantation, and immunotherapy. This review summarizes the most recent advances in NEC treatment currently underway as well as their applicability and associated challenges and limitations, with the aim to provide new insight into the paradigm of care for NEC worldwide.

Effect of Liposomal-Lactoferrin-Based Eye Drops on the Conjunctival Microflora of Patients Undergoing Cataract Surgery

INTRODUCTION

Postoperative endophthalmitis is typically caused by the patient's conjunctival bacterial flora. Povidone iodine solution (5%) is used perioperatively to obtain periocular and ocular antisepsis. However, an adjunctive prophylaxis procedure could further help control the conjunctival microbial load. Considering the increase in antibiotic resistance, a progressive shift toward alternative methods would be desirable. Somilux^® eye drops (Alfa Intes, lactoferrin-based eye drops) are medical devices containing liposomal lactoferrin (LF). This study evaluates the effects on conjunctival microflora of LF-based eye drops used in the preoperative phase in patients scheduled for cataract surgery.

METHODS

LF-based eye drops or a vehicle solution (water solution) were instilled 4 times a day starting 3 days before cataract surgery. Before the therapy (T0) and at the time of surgery (T1), a conjunctival swab was performed in both eyes and processed to detect microbial growth, microbiological isolation, and species identification. The outcome was the quantification and characterization of the local microbial flora before and after using LF-based or vehicle-based eye drops. Safety of the treatments was also evaluated.

RESULTS

88 eyes of 44 patients (mean [± SD] age 75 [± 12.6] years) were enrolled. At baseline, 54 conjunctival swabs showed only saprophytic flora, 27 showed only potential pathogenic flora, and seven showed both of them. LF-based eye drops reduced the proportion of potentially pathogenic bacteria (36% at T0 vs. 9% at T1, p = 0.008) compared with the vehicle (41% at T0 vs. 55% at T1, p = 0.302) without altering the physiological ocular microbial composition. No adverse events have been reported.

CONCLUSION

Our findings provide a novel contribution to the scientific knowledge on the role of LF in the ophthalmic field, supporting the use of LF-based eye drops as a safe and selective treatment to improve the ocular surface physiological defenses and control the bacterial ocular surface contamination prior to cataract surgery.

Probiotics to prevent necrotizing enterocolitis and reduce mortality in neonates: A meta-analysis

BACKGROUND

Probiotics are gradually being used as a supplementation to prevent necrotizing enterocolitis (NEC) and reduce mortality in neonates. We performed an updated meta-analysis to systematically evaluate the efficacy and safety of prophylactic probiotic supplementation for preventing NEC.

METHODS

The databases including PubMed, Embase, Scopus, Web of Science, and China National Knowledge Infrastructure were used to search the relevant articles. The latest retrieval date was up to December 2021. The meta-analysis was performed using Stata version 10.0. Finally, a total of 70 studies containing 8319 cases and 9283 controls were included. The strength of the association between the supplementation of probiotics and NEC was measured by risk ratios (RRs) with 95% confidence intervals (CIs). Pooled effect sizes across studies were performed by a random effect model.

RESULTS

The results showed that the probiotics could significantly reduce the incidence of NEC (stage II or more) (RR = 0.436, 95% CI = 0.357-0.531, P < .001), the overall mortality (RR = 0.651, 95% CI = 0.506-0.836, P < .001), and NEC-related mortality (RR = 0.639, 95% CI = 0.423-0.966, P = .034). Due to the lack of sufficient sample size, we did not perform the subgroup analysis by types of probiotic strain.

CONCLUSION

This meta-analysis indicates that the use of probiotics can effectively reduce the occurrence of NEC and mortality in neonates.

Probiotics to prevent necrotizing enterocolitis in very low birth weight infants: A network meta-analysis

Objective

This study aims to review the evidence for the optimal regimen of probiotics for the prevention of necrotizing enterocolitis (NEC) in very low birth weight infants.

Design

Through searching PubMed, EMBASE, Cochrane Library, and Web of Science till September 30, 2022, only randomized controlled trials were included to evaluate the optimal regimen of probiotics for the prevention of NEC in very low birth weight infants. The methodological quality of the included studies was assessed by the Cochrane risk of bias assessment tool (RoB 2), and the collected data were analyzed accordingly using Stata software.

Results

Twenty-seven RCTs were included, and the total sample size used in the study was 529. The results of the network meta-analysis showed that Bovine lactoferrin + Lactobacillus rhamnosus GG (RR 0.03; 95% CI 0.00-0.35), Lactobacillus rhamnosus + Lactobacillus plantarum + Lactobacillus casei + Bifidobacterium lactis (RR 0.06; 95% CI 0.00-0.70), Bifidobacterium lactis + inulin (RR 0.16; 95% CI 0.03-0.91) were superior to the control group (Bifidobacterium lactis + Bifidobacterium longum) in reducing the incidence of NEC. The reduction in the incidence of NEC were as follows: Bovine lactoferrin + Lactobacillus rhamnosus GG (SUCRA 95.7%) > Lactobacillus rhamnosus + Lactobacillus plantarum + Lactobacillus casei + Bifidobacterium lactis (SUCRA 89.4%) > Bifidobacterium lactis + inulin (SUCRA 77.8%).

Conclusions

This network meta-analysis suggests that Lactobacillus rhamnosus GG combined with bovine lactoferrin maybe the most recommended regimen for the prevention of NEC in very low birth weight infants.

Peptide Tat(48-60) YVEEL protects against necrotizing enterocolitis through inhibition of toll-like receptor 4-mediated signaling in a phosphatidylinositol 3-kinase/AKT dependent manner

Necrotizing enterocolitis (NEC) is a catastrophic disease largely occurring in preterm infants, and toll-like receptor 4 (TLR4) has been implicated in its pathogenesis. The current therapeutic strategies for NEC are, however, far from optimal. In the present study, a whey-derived antioxidative peptide conjugated with a cell-penetrating TAT [^{Tat (48-60)} YVEEL] was prepared to endow it with enhanced cell uptake capability and bioavailability. The protective effect of ^{Tat (48-60)} YVEEL on experimental NEC was evaluated both in vitro and in vivo. Inhibition of TLR4-mediated signaling by ^{Tat (48-60)} YVEEL was assessed in FHC and IEC-6 enterocytes, neonatal rat model of NEC, and the mechanism underlying this effect was determined. ^{Tat (48-60)} YVEEL significantly inhibited TLR4-mediated expression of pro-inflammatory cytokines, p65 nuclear translocation and restored the impaired enterocyte migration in cultured enterocytes. In addition, ^{Tat (48-60)} YVEEL administration strikingly increased the survival rate, and reduced the severity of NEC in rats through inhibition of TLR4-mediated signaling. These protective effects of ^{Tat (48-60)} YVEEL occurred in a PI3K/AKT dependent manner, as administration of PI3K activator Ys49 abrogated its protective effects. Combined with liposomes, ^{Tat (48-60)} YVEEL demonstrated longer retention in the intestines that better for potential clinical applications. These data demonstrate that ^{Tat (48-60)} YVEEL protects against NEC through inhibition of TLR4-mediated signaling in a PI3K/AKT dependent manner, and offer a potential therapeutic approach to this disease.

Oral Lactoferrin Supplementation during Induction Chemotherapy Promotes Gut Microbiome Eubiosis in Pediatric Patients with Hematologic Malignancies

Induction chemotherapy is the first-line treatment for pediatric patients with hematologic malignancies. However, several complications may arise, mainly infections and febrile neutropenia, with a strong impact on patient morbidity and mortality. Such complications have been shown to be closely related to alterations of the gut microbiome (GM), making the design of strategies to foster its eubiosis of utmost clinical importance. Here, we evaluated the impact of oral supplementation of lactoferrin (LF), a glycoprotein endowed with anti-inflammatory, immunomodulatory and antimicrobial activities, on GM dynamics in pediatric oncohematologic patients during induction chemotherapy. Specifically, we conducted a double blind, placebo-controlled trial in which GM was profiled through 16S rRNA gene sequencing before and after two weeks of oral supplementation with LF or placebo. LF was safely administered with no adverse effects and promoted GM homeostasis by favoring the maintenance of diversity and preventing the bloom of pathobionts (e.g., Enterococcus). LF could, therefore, be a promising adjunct to current therapeutic strategies in these fragile individuals to reduce the risk of GM-related complications.

Necrotising enterocolitis, late-onset sepsis and mortality after routine probiotic introduction in the UK

OBJECTIVE

To compare necrotising enterocolitis (NEC), late-onset sepsis (LOS), focal intestinal perforation (FIP) and mortality in infants from a single neonatal unit before and after probiotic introduction.

DESIGN

Retrospective review of infants <32 weeks admitted January 2009-December 2012 (no probiotic) and January 2013-December 2017 (routine probiotics). Infants included were admitted before day 3, and not transferred out before day 3. NEC, LOS and FIP were defined with standard definitions.

PATIENTS

1061 infants were included, 509 preprobiotic and 552 postprobiotic. Median gestation, birth weight and antenatal steroid use did not differ, and proportions of extremely low birthweight infants were similar (37% and 41%).

RESULTS

Overall unadjusted risk of NEC (9.2% (95% CI 7.1 to 12.1) vs 10.6% (95% CI 8.2 to 13.4), p=0.48), LOS (16.3% (95% CI 13.2 to 19.6) vs 14.1% (95% CI 11.5 to 17.4), p=0.37) and mortality (9.2% (95% CI 7.1 to 12.1) vs 9.7% (95% CI 7.6 to 12.6), p=0.76) did not differ, nor proportion of surgical NEC. In multiple logistic regression, accounting for gestation, birth weight, antenatal steroid, maternal milk, chorioamnionitis and sex, probiotic receipt was not significantly associated with NEC (adjusted OR (aOR) 1.08 (95% CI 0.71 to 1.68), p=0.73), LOS or mortality. In subgroup (645 infants) >28 weeks, aOR for NEC in the probiotic cohort was 0.42 (95% CI 0.2 to 0.99, p=0.047). FIP was more common in the probiotic cohort (OR 2.3 (95% CI 1.0 to 5.4), p=0.04), not significant in regression analysis (2.11 (95% CI 0.97 to 4.95), p=0.05).

CONCLUSIONS

Probiotic use in this centre did not reduce overall mortality or rates of NEC, LOS or FIP but subgroup analysis identified NEC risk reduction in infants >28 weeks, and LOS reduction <28 weeks.

The Lactoferrin Phenomenon-A Miracle Molecule

Numerous harmful factors that affect the human body from birth to old age cause many disturbances, e.g., in the structure of the genome, inducing cell apoptosis and their degeneration, which leads to the development of many diseases, including cancer. Among the factors leading to pathological processes, microbes, viruses, gene dysregulation and immune system disorders have been described. The function of a protective agent may be played by lactoferrin as a “miracle molecule”, an endogenous protein with a number of favorable antimicrobial, antiviral, antioxidant, immunostimulatory and binding DNA properties. The purpose of this article is to present the broad spectrum of properties and the role that lactoferrin plays in protecting human cells at all stages of life.

A Narrative Review on Efficacy and Safety of Proton Pump Inhibitors in Children

Proton pump inhibitors (PPIs) are among the most prescribed drugs worldwide and include omeprazole, esomeprazole, lansoprazole, pantoprazole, and rabeprazole. Their use in pediatrics is approved for children older than 1 year, for the short-term treatment of symptomatic gastroesophageal reflux disease (GERD), healing of erosive esophagitis, treatment of peptic ulcer disease, and eradication of Helicobacter pylori. PPIs are also considered the standard of care for pediatric eosinophilic esophagitis. Despite the strict range of indications, the use of this class of molecules has increased in all pediatric age ranges. The long-term gastric acid suppression in children has been linked to increased risks of gastrointestinal and lower respiratory tract infections, bone fractures, and allergy. This study aims to provide a comprehensive overview of the mechanism of actions, use (and misuse) in infants and children, and safety of PPIs.

Effectiveness of two probiotics in preventing necrotising enterocolitis in a cohort of very-low-birth-weight premature new-borns

According to previous research, the incidence of necrotising enterocolitis (NEC) decreases after supplementation with probiotics. However, few studies have considered the equivalence or otherwise of different strains of probiotics in this respect. Accordingly, this prospective observational study was conducted in a cohort of 245 very-low-birth-weight (VLBW) new-borns to assess the prevalence of NEC after supplementation with the probiotic Inforan^® (Berna Biotech, Madrid, Spain) 250 mg capsules containing 10⁹ cfu of Lactobacillus acidophilus (ATCC 4356) and 10⁹ cfu of Bifidobacterium bifidum (ATCC 15696); or with Bivos^® (Ferring, Madrid, Spain) containing Lacticaseibacillus (formerly Lactobacillus) rhamnnosus (LGG) (ATCC 53103) (10⁹ cfu); or with no probiotic supplementation. Statistical analysis was performed using multivariant regression for the duration of parenteral nutrition, length of neonatal intensive care unit stay, use of oxygen therapy and presence of chorioamnionitis. Of the VLBW new-borns in the study group, 65 received Infloran, 108 received Bivos and 72 received no probiotic. A significant association was observed between a reduced presence of NEC Stage ≥2 and probiotic supplementation. The odds risk (OR) obtained was 0.174 (95% confidence interval (CI): 0.032-0.936) for Infloran and 0.196 (95%CI: 0.053-0.732) for Bivos. Therefore, both probiotics are associated with a lower prevalence of NEC in VLBW new-borns, with no significant differences.

Is Lactoferrin Supplementation Beneficial for All Preterm Infants?

OBJECTIVE

 Human milk (HM) has antibacterial properties due to the presence of immune-modulators, including lactoferrin (LF). This study will determine effect(s) of HM maturation, fortification, and storage conditions on LF levels and its antibacterial properties.

STUDY DESIGN

 HM samples (n = 30) were obtained from preterm and term mothers. The LF levels were analyzed by ELISA, and the antibacterial activity was measured after inoculation with Escherichia coli.

RESULTS

 The highest level of LF in preterm HM was observed in the first week of lactation. However, storage of preterm HM at 4°C decreased LF levels significantly. Both LF levels and antibacterial activity in preterm HM was lower compared with term HM, but significantly higher than donor HM even after HM-based fortification. LF supplementation of donor HM improved its antibacterial activity.

CONCLUSION

 Preterm infants fed donor HM, formula, or stored HM at 4°C may benefits from LF supplementation to improve HM antibacterial properties.

KEY POINTS

· Milk LF levels vary with storage and maturity.. · Donor milk is deficient in LF even after adding HM-based fortification.. · Donor HM and formula fed infants may benefit from LF..

Antibacterial and Anti-biofilm Activity of the Human Breast Milk Glycoprotein Lactoferrin against Group B Streptococcus

Group B Streptococcus (GBS) is an encapsulated Gram-positive human pathogen that causes invasive infections in pregnant hosts and neonates, as well as immunocompromised individuals. Colonization of the human host requires the ability to adhere to mucosal surfaces and circumnavigate the nutritional challenges and antimicrobial defenses associated with the innate immune response. Biofilm formation is a critical process to facilitate GBS survival and establishment of a replicative niche in the vertebrate host. Previous work has shown that the host responds to GBS infection by producing the innate antimicrobial glycoprotein lactoferrin, which has been implicated in repressing bacterial growth and biofilm formation. Additionally, lactoferrin is highly abundant in human breast milk and could serve a protective role against invasive microbial pathogens. This study demonstrates that human breast milk lactoferrin has antimicrobial and anti-biofilm activity against GBS and inhibits its adherence to human gestational membranes. Together, these results indicate that human milk lactoferrin could be used as a prebiotic chemotherapeutic strategy to limit the impact of bacterial adherence and biofilm formation on GBS-associated disease outcomes.

Prophylactic Probiotic Supplementation for Preterm Neonates-A Systematic Review and Meta-Analysis of Nonrandomized Studies

Systematic review and meta-analyses of randomized controlled trials (RCTs) show that probiotics reduce the risk of necrotizing enterocolitis (NEC ≥ Stage II), late onset sepsis (LOS), all-cause mortality, and feeding intolerance in preterm neonates. Data from observational studies is important to confirm probiotic effects in clinical practice. We aimed to compare outcomes before and after implementing routine probiotic supplementation (RPS) in preterm neonates (<37 weeks of gestation) by performing a systematic review of non-RCTs using Cochrane methodology. Databases including PubMed, The Cumulative Index to Nursing and Allied Health Literature (CINAHL), Embase, Cochrane Central library, and Google Scholar were searched in May 2020. A meta-analysis was performed using a random effects model. Categorical measure of effect size was expressed as OR and 95% CI. Statistical heterogeneity was assessed by the chi-squared test, I2 statistic. The level of evidence (LOE) was summarized using GRADE (Grading of Recommendations Assessment, Development, and Evaluation) guidelines. Primary outcomes were NEC ≥ Stage II, LOS, and all-cause mortality. Secondary outcomes included probiotic sepsis. Thirty good-quality non-RCTs (n = 77,018) from 18 countries were included. The meta-analysis showed RPS was associated with significantly reduced: 1) NEC ≥ Stage II (30 studies, n = 77,018; OR: 0.60; 95% CI: 0.50, 0.73; P <0.00001, I2: 65%; LOE: Moderate), 2) LOS: (21 studies, n = 65,858; OR: 0.85; 95% CI: 0.74, 0.97; P = 0.02, I2: 74%; LOE: Low), and 3) all-cause mortality (27 non-RCTs, n = 70,977; OR: 0.77; 95% CI: 0.68, 0.88; P = 0.0001, I2: 49%; LOE: Low). Subgroups: 1) extremely low birth weight (ELBW: birth weight <1000 g) neonates: RPS was associated with significantly reduced NEC ≥ Stage II (4.5% compared with 7.9%). However, there was no difference in LOS and mortality. 2) Multistrain RPS was more effective than single strain. One study reported 3 nonfatal cases of probiotic sepsis. In summary, moderate- to low-quality evidence indicates that RPS was associated with significantly reduced NEC ≥ Stage II, LOS, and all-cause mortality in neonates <37 weeks of gestation and NEC ≥ Stage II in ELBW neonates.

Bioactive proteins in bovine colostrum and effects of heating, drying and irradiation

Bovine colostrum (BC) contains bioactive proteins, such as immunoglobulin G (IgG), lactoferrin (LF) and lactoperoxidase (LP). BC was subjected to low-temperature, long-time pasteurization (LTLT, 63 °C, 30 min) or high-temperature, short-time pasteurization (HTST, 72 °C, 15 s) and spray-drying (SD), with or without γ-irradiation (GI, ∼14 kGy) to remove microbial contamination. Relative to unpasteurized liquid BC, SD plus GI increased protein denaturation by 6 and 11%, respectively, increasing to 19 and 27% after LTLT and to 48% after HTST, with no further effects after GI (all P < 0.05). LTLT, without or with GI, resulted in 15 or 29% denaturation of IgG, compared with non-pasteurized BC, and 34 or 58% for HTST treatment (all P < 0.05, except LTLT without GI). For IgG, only GI, not SD or LTLT, increased denaturation (30-38%, P < 0.05) but HTST increased denaturation to 40%, with further increases after GI (60%, P < 0.05). LTLT and HTST reduced LP levels (56 and 81% respectively) and LTLT reduced LF levels (21%), especially together with GI (47%, P < 0.05). Denaturation of BSA, β-LgA, β-LgB and α-La were similar to IgG. Methionine, a protective amino acid against free oxygen radicals, was oxidised by LTLT + GI (P < 0.05) while LTLT and HTST had no effect. Many anti-inflammatory proteins, including serpin anti-proteinases were highly sensitive to HTST and GI but preserved after LTLT pasteurization. LTLT, followed by SD is an optimal processing technique preserving bioactive proteins when powdered BC is used as a diet supplement for sensitive patients.

NEC-like intestinal injury is ameliorated by Lactobacillus rhamnosus GG in parallel with SIGIRR and A20 induction in neonatal mice

BACKGROUND

Exaggerated Toll-like receptor (TLR) signaling and intestinal dysbiosis are key contributors to necrotizing enterocolitis (NEC). Lactobacillus rhamnosus GG (LGG) decreases NEC in preterm infants, but underlying mechanisms of protection remain poorly understood. We hypothesized that LGG alleviates dysbiosis and upregulates TLR inhibitors to protect against TLR-mediated gut injury.

METHODS

Effects of LGG (low- and high-dose) on intestinal pro-inflammatory TLR signaling and injury in neonatal mice subjected to formula feeding (FF) and NEC were determined. 16S sequencing of stool and expression of anti-TLR mediators SIGIRR (single immunoglobulin interleukin-1-related receptor) and A20 were analyzed.

RESULTS

FF induced mild intestinal injury with increased expression of interleukin-1β (IL-1β) and Kupffer cell (KC) (mouse homolog of IL-8) compared to controls. LGG decreased IL-1β and KC in association with attenuated TLR signaling and increased SIGIRR and A20 expression in a dose-dependent manner. Low- and high-dose LGG had varying effects on gut microbiome despite both doses providing gut protection. Subsequent experiments of LGG on NEC revealed that pro-inflammatory TLR signaling and intestinal injury were also decreased, and SIGIRR and A20 expression increased, in a dose-dependent manner with LGG pre-treatment.

CONCLUSIONS

LGG protects against intestinal TLR-mediated injury by upregulating TLR inhibitors without major changes in gut microbiome composition.

Effect of bovine lactoferrin on prevention of late-onset sepsis in infants <1500 g: a pooled analysis of individual patient data from two randomized controlled trials

We previously conducted two randomized controlled trials with bovine lactoferrin (bLF) for the prevention of late-onset sepsis (LOS) in infants with a birth weight <2500 g (Study 1) and <2000 g (Study 2). The aim of this study was to determine the preventative effects of bLF on culture-proven or probable LOS in infants with a birth weight <1500 g from both studies, and to determine the effect of bLF in relation to intake of human milk. Both trial designs had similar inclusion and exclusion criteria, the same dose of bLF [200 mg·(kg body mass)^-1·day^-1], and used the same control (maltodextrin). We fitted multivariate Cox regression models to estimate the effect of bLF on the risk of development of the composite outcome, adjusting for covariates. We included 335 neonates with a mean birth weight of 1162 ± 244 g; 27.5% were <1000 g. There were 33 first episodes of LOS in the bLF treatment group and 48 in the control group (19.5% vs. 28.9%). bLF had a protective effect on the risk of development of LOS [hazard ratio (HR) = 0.64; %95 CI = 0.41-0.99; p = 0.048]; particularly among infants weighing <1000 g [HR = 0.46; %95 CI = 0.22-0.96; p = 0.039] and infants with a low intake of human milk [HR = 0.40; %95 CI = 0.19-0.84; p = 0.015]. Therefore, bLF supplementation protects infants <1500 g from LOS, particularly those infants not receiving human milk.

Probiotics and Human Milk Oligosaccharides in Premature Infants

Intestinal dysbiosis precedes and is a likely causative factor in necrotizing enterocolitis (NEC) and many cases of late-onset sepsis. Randomized controlled trials and observational cohort studies demonstrate decreased risk of NEC, sepsis, and death with the administration of probiotic microbes and decreased risk of NEC and sepsis with feeding of human milk. Animal studies suggest promising mechanisms by which probiotic microbes and human milk oligosaccharides alter the composition of the intestinal microbiota and may prevent disease in premature infants. Inclusion of parents in discussions of the risks and benefits of human milk and probiotics for premature infants is essential.

Lactoferrin from Bovine Milk: A Protective Companion for Life

Lactoferrin (Lf), an iron-binding multifunctional glycoprotein belonging to the transferrin family, is present in most biological secretions and reaches particularly high concentrations in colostrum and breast milk. A key function of lactoferrin is non-immune defence and it is considered to be a mediator linking innate and adaptive immune responses. Lf from bovine milk (bLf), the main Lf used in human medicine because of its easy availability, has been designated by the United States Food and Drug Administration as a food additive that is generally recognized as safe (GRAS). Among the numerous protective activities exercised by this nutraceutical protein, the most important ones demonstrated after its oral administration are: Antianemic, anti-inflammatory, antimicrobial, immunomodulatory, antioxidant and anticancer activities. All these activities underline the significance in host defence of bLf, which represents an ideal nutraceutical product both for its economic production and for its tolerance after ingestion. The purpose of this review is to summarize the most important beneficial activities demonstrated following the oral administration of bLf, trying to identify potential perspectives on its prophylactic and therapeutic applications in the future.

The effects of proton pump inhibitors on the microbiome in young children

AIM

The use of proton pump inhibitor (PPI) treatments are increasing among paediatric patients worldwide. We aimed to review the effects of PPIs on the microbiome and its associated effect on the gastrointestinal, respiratory and metabolic systems. The role of probiotics is discussed.

METHODS

We searched for relevant articles published in English language in PubMed and Google Scholar. Articles were extracted using subject heading and key words of interest to the topic.

RESULTS

There is evidence that PPIs modify the microbiome of the mouth, gut and lungs. The specific adverse effects associated with PPIs were necrotising enterocolitis, late onset sepsis in premature infants, Clostridium difficile infection, asthma, obesity and small intestine bacterial overgrowth in young children. Studies on the use of probiotics to counteract adverse effects of PPIs were limited.

CONCLUSION

PPIs create dysbiosis of the microbiome in the mouth, gut and lungs in the paediatric population. Probiotics could restore dysbiosis but it has very poorly been studied if probiotics can counteract or prevent PPI induced adverse effects.

Synbiotics use for preventing sepsis and necrotizing enterocolitis in very low birth weight neonates: a randomized controlled trial

BACKGROUND

Probiotics and prebiotics have strain-specific effects on the host. Synbiotics, a mixture of probiotics and prebiotics, are proposed to have more beneficial effects on the host than either agent has alone.

PURPOSE

We performed a randomized controlled trial to investigate the effect of Lactobacillus and Bifidobacterium together with oligosaccharides and lactoferrin on the development of necrotizing enterocolitis (NEC) or sepsis in very low birth weight neonates.

METHODS

Neonates with a gestational age ≤32 weeks and birth weight ≤1,500 g were enrolled. The study group received a combination of synbiotics and lactoferrin, whereas the control group received 1 mL of distilled water as placebo starting with the first feed until discharge. The outcome measures were the incidence of NEC stage ≥2 or late-onset cultureproven sepsis and NEC stage ≥2 or death.

RESULTS

Mean birth weight and gestational age of the study (n=104) and the control (n=104) groups were 1,197±235 g vs. 1,151±269 g and 29±1.9 vs. 28±2.2 weeks, respectively (P>0.05). Neither the incidence of NEC stage ≥2 or death, nor the incidence of NEC stage ≥2 or late-onset culture-proven sepsis differed between the study and control groups (5.8% vs. 5.9%, P=1; 26% vs. 21.2%, P=0.51). The only significant difference was the incidence of all stages of NEC (1.9% vs. 10.6%, P=0.019).

CONCLUSION

The combination of synbiotics and lactoferrin did not reduce NEC severity, sepsis, or mortality.

Probiotics and Preterm Infants: A Position Paper by the European Society for Paediatric Gastroenterology Hepatology and Nutrition Committee on Nutrition and the European Society for Paediatric Gastroenterology Hepatology and Nutrition Working Group for Probiotics and Prebiotics

More than 10,000 preterm infants have participated in randomised controlled trials on probiotics worldwide, suggesting that probiotics in general could reduce rates of necrotising enterocolitis (NEC), sepsis, and mortality. Answers to relevant clinical questions as to which strain to use, at what dosage, and how long to supplement are, however, not available. On the other hand, an increasing number of commercial products containing probiotics are available from sometimes suboptimal quality. Also, a large number of units around the world are routinely offering probiotic supplementation as the standard of care despite lacking solid evidence. Our recent network meta-analysis identified probiotic strains with greatest efficacy regarding relevant clinical outcomes for preterm neonates. Efficacy in reducing mortality and morbidity was found for only a minority of the studied strains or combinations. In the present position paper, we aim to provide advice, which specific strains might potentially be used and which strains should not be used. In addition, we aim to address safety issues of probiotic supplementation to preterm infants, who have reduced immunological capacities and occasional indwelling catheters. For example, quality reassurance of the probiotic product is essential, probiotic strains should be devoid of transferable antibiotic resistance genes, and local microbiologists should be able to routinely detect probiotic sepsis. Provided all safety issues are met, there is currently a conditional recommendation (with low certainty of evidence) to provide either Lactobacillus rhamnosus GG ATCC53103 or the combination of Bifidobacterium infantis Bb-02, Bifidobacterium lactis Bb-12, and Streptococcus thermophilus TH-4 in order to reduce NEC rates.

Lactobacillus rhamnosus sepsis associated with probiotic therapy in an extremely preterm infant: Pathogenesis and a review for clinicians

BACKGROUND

Necrotizing enterocolitis (NEC) is one of the most serious complications in preterm infants. Probiotics have been used to prevent NEC. Safety is a major concern for this practice.

METHODS

We reported a female preterm infant who received oral Lactobacillus rhamnosus GG but developed sepsis 12 days after the treatment. Cultures of blood and the catheter tip yielded L. rhamnosus. Next-generation sequencing was performed to analyze isolates from blood, stool, catheter, and product capsules. We also determined the capacities of these isolates to form biofilms. A literature review was performed.

RESULTS

The patient was treated with ampicillin and piperacillin/tazobactam, and she subsequently recovered without complications. The analysis of genome sequences indicated that all the isolates belonged to the clone of L. rhamnosus GG (ATCC 53103), suggesting that sepsis was a catheter-related infection caused by the oral probiotic. L. rhamnosus GG (ATCC 53103) and the probiotic strain tested formed biofilms under all growth conditions. Isolates from the blood and catheter tip also formed biofilms, but the stool isolate did not. The capacity of intrinsic biofilm formation in L. rhamnosus GG depended on environmental factors and the type of culture medium. Literature review of L. rhamnosus GG sepsis in preterm and young infants found that nearly 60% of the patients had a suspected or confirmed infected catheter.

CONCLUSION

The study showed that the capacity of L. rhamnosus GG to form biofilms, especially in the presence of glucose, is a critical factor leading to the probiotic-related sepsis in preterm infants.

Enteral lactoferrin supplementation for prevention of sepsis and necrotizing enterocolitis in preterm infants

BACKGROUND

Lactoferrin, a normal component of human colostrum and milk, can enhance host defenses and may be effective for prevention of sepsis and necrotizing enterocolitis (NEC) in preterm neonates.

OBJECTIVES

To assess the safety and effectiveness of lactoferrin supplementation to enteral feeds for prevention of sepsis and NEC in preterm neonates. Secondarily, we assessed the effects of lactoferrin supplementation to enteral feeds on the duration of positive-pressure ventilation, development of chronic lung disease (CLD) or periventricular leukomalacia (PVL), length of hospital stay to discharge among survivors, and adverse neurological outcomes at two years of age or later.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to update our search. We searched the Cochrane Central Register of Controlled Trials (CENTRAL 2019, Issue 9), MEDLINE via PubMed (1966 to 20 January 2020), PREMEDLINE (1996 to 20 January 2020), Embase (1980 to 20 January 2020), and CINAHL (1982 to 20 January 2020). We also searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomized controlled trials and quasi-randomized trials.

SELECTION CRITERIA

In our search, we included randomized controlled trials (RCTs) evaluating enteral lactoferrin supplementation at any dose or duration to prevent sepsis or NEC in preterm neonates.

DATA COLLECTION AND ANALYSIS

We used the standard methods of Cochrane Neonatal and the GRADE approach to assess the certainty of evidence.

MAIN RESULTS

Meta-analysis of data from twelve randomized controlled trials showed that lactoferrin supplementation to enteral feeds decreased late-onset sepsis (typical RR 0.82, 95% CI 0.74 to 0.91; typical RD -0.04, 95% CI, -0.06, -0.02; NNTB 25, 95% CI 17 to 50; 12 studies, 5425 participants, low-certainty evidence) and decreased length of hospital stay (MD -2.38, 95% CI, -4.67, -0.09; 3 studies, 1079 participants, low-certainty evidence). Sensitivity analysis including only good methodological certainty studies suggested a decrease in late-onset sepsis with enteral lactoferrin supplementation (typical RR 0.87, 95% CI, 0.78, 0.97; typical RD -0.03, 95% CI, -0.05, -0.0; 9 studies, 4702 participants, low-certainty evidence). There were no differences in NEC stage II or III (typical RR 1.10, 95% CI, 0.86, 1.41; typical RD -0.00, 95% CI, -0.02, 0.01; 7 studies, 4874 participants; low-certainty evidence) or 'all-cause mortality' (typical RR 0.90, 95% CI 0.69, 1.17; typical RD -0.00, 95% CI, -0.01, 0.01; 11 studies, 5510 participants; moderate-certainty evidence). One study reported no differences in neurodevelopmental testing by Mullen's or Bayley III at 24 months of age after enteral lactoferrin supplementation (one study, 292 participants, low-certainty evidence). Lactoferrin supplementation to enteral feeds with probiotics decreased late-onset sepsis (RR 0.25, 95% CI 0.14 to 0.46; RD -0.13, 95% CI -0.18 to -0.08; NNTB 8, 95% CI 6 to 13; 3 studies, 564 participants; low-certainty evidence) and NEC stage II or III (RR 0.04, 95% CI 0.00 to 0.62; RD -0.05, 95% CI -0.08 to -0.03; NNTB 20, 95% CI 12.5 to 33.3; 1 study, 496 participants; very low-certainty evidence), but not 'all-cause mortality' (very low-certainty evidence). Lactoferrin supplementation to enteral feeds with or without probiotics had no effect on CLD, duration of mechanical ventilation or threshold retinopathy of prematurity (low-certainty evidence). Investigators reported no adverse effects in the included studies.

AUTHORS' CONCLUSIONS

We found low-certainty evidence from studies of good methodological quality that lactoferrin supplementation of enteral feeds decreases late-onset sepsis but not NEC ≥ stage II or 'all cause mortality' or neurodevelopmental outcomes at 24 months of age in preterm infants without adverse effects. Low- to very low-certainty evidence suggests that lactoferrin supplementation of enteral feeds in combination with probiotics decreases late-onset sepsis and NEC ≥ stage II in preterm infants without adverse effects, however, there were few included studies of poor methodological quality. The presence of publication bias and small studies of poor methodology that may inflate the effect size make recommendations for clinical practice difficult.

Sepsis: From Historical Aspects to Novel Vistas. Pathogenic and Therapeutic Considerations

BACKGROUND

Sepsis is a clinical condition due to an infectious event which leads to an early hyper-inflammatory phase followed by a status of tolerance or immune paralysis. Hyper-inflammation derives from a massive activation of immune (neutrophils, monocytes/macrophages, dendritic cells and lymphocytes) and non-immune cells (platelets and endothelial cells) in response to Gram-negative and Gram-positive bacteria and fungi.

DISCUSSION

A storm of pro-inflammatory cytokines and reactive oxygen species accounts for the systemic inflammatory response syndrome. In this phase, bacterial clearance may be associated with a severe organ failure development. Tolerance or compensatory anti-inflammatory response syndrome (CARS) depends on the production of anti-inflammatory mediators, such as interleukin-10, secreted by T regulatory cells. However, once triggered, CARS, if prolonged, may also be detrimental to the host, thus reducing bacterial clearance.

CONCLUSION

In this review, the description of pathogenic mechanisms of sepsis is propaedeutic to the illustration of novel therapeutic attempts for the prevention or attenuation of experimental sepsis as well as of clinical trials. In this direction, inhibitors of NF-κB pathway, cell therapy and use of dietary products in sepsis will be described in detail.

Probiotics for Prevention of Severe Necrotizing Enterocolitis: Experience of New Zealand Neonatal Intensive Care Units

Introduction: Necrotizing enterocolitis (NEC) affects mainly preterm infants, has a multifactorial etiology and is associated with intestinal dysbiosis and disordered immunity. Use of probiotics for prophylaxis is beneficial with studies indicating reduction in NEC ≥ stage 2, late onset sepsis (LOS) and mortality. However, not all studies have shown a reduction, there are questions regarding which probiotic to use, whether infants <1,000 g benefit and the risk of probiotic sepsis. All neonatal intensive care units in New Zealand (NZ) use probiotics and contribute to an international database (Australian and New Zealand Neonatal Network or ANZNN). Objective: To use ANZNN data to investigate the experience of NZ neonatal units with probiotics for NEC prevention in a setting where the baseline incidence of severe NEC was low, to compare results of 2 commonly used probiotic regimes and report on the extremely low birth weight subgroup. Method: Outcomes before (Pre group 2007-2010) and after (Probiotic group 2013-2015) starting routine probiotics for preterm infants <1,500 g or <32 weeks were compared. Clinicians reviewed cases to ensure they met database criteria. Five units used Infloran (Bifidobacterium bifidum and Lactobacillus acidophilus) and 1 unit used Lactobacillus GG (LGG) and bovine lactoferrin (bLF). Results: Four thousand five hundred and twenty nine infants were included and Pre and Probiotic groups were well-balanced with regard to gestation, birth weight and gender. The incidence of NEC in the Probiotic group was 1.6 and 2.7% in the pre group (corrected OR 0.62 CI 0.41-0.94). There was one case of probiotic sepsis. There was no significant difference between the Infloran and LGG/bLF combinations in regard to observed NEC rates. Late onset sepsis rates were significantly lower in the Probiotic group (p < 0.01). Conclusions: Introduction of probiotics for preterm infants in NZ has been associated with significant reductions in NEC and late onset sepsis.

Mixed probiotics decrease the incidence of stage II-III necrotizing enterocolitis and death: A systematic review and meta-analysis

BACKGROUND

Necrotizing enterocolitis (NEC) is a major cause of morbidity and mortality in premature infants. In order to evaluate the efficacy of probiotics in the prevention of stage II-III NEC, we performed a meta-analysis of clinical studies.

METHODS

We searched in PubMed, Medline and Embase from 1 January 1990 to 16 January 2018. Heterogeneity was examined by Q-test. Publication bias was evaluated by funnel plot and Egger's regression test.

RESULTS

30 articles were identified meeting the inclusion criteria. Data showed that probiotics supplement could significantly reduce the risk of stage II-III NEC (RR = 0.51, 95% CI, 0.38 to 0.67, P < 0.001) and death rate (RR = 0.69, 95% CI, 0.55 to 0.87, P = 0.002). The mixed probiotics and lactobacillus could reduce the risk of stage II-III NEC (for mixed probiotics, RR = 0.39, 95% CI, 0.26 to 0.57; for lactobacillus, RR = 0.53, 95% CI, 0.36 to 0.78), while bifidobacterium or saccharomyces did not have such effect. The results also indicated that only the mixed probiotics could reduce the risk of deaths (RR = 0.52, 95%CI, 0.34 to 0.80). Subgroup analysis for mortality revealed that probiotics had significant effect in Asian region (RR = 0.54, 95% CI, 0.37 to 0.80, P = 0.002) but not in non-Asian region (RR = 0.84, 95% CI, 0.66 to 1.08, P = 0.179).

CONCLUSIONS

Probiotics could significantly decrease the risk of stage II-III NEC and death. Compared to using single probiotics species, the application of combining different probiotics has a better efficacy in the prevention of stage II-III NEC and death, especially in the Asian population.

The Impact of Lactoferrin on the Growth of Intestinal Inhabitant Bacteria

Lactoferrin (Lf) is an iron-binding milk glycoprotein that promotes the growth of selected probiotic strains. The effect of Lf on the growth and diversification of intestinal microbiota may have an impact on several issues, including (i) strengthening the permeability of the epithelial cell monolayer, (ii) favoring the microbial antagonism that discourages the colonization and proliferation of enteric pathogens, (iii) enhancing the growth and maturation of cell-monolayer components and gut nerve fibers, and (iv) providing signals to balance the anti- and pro-inflammatory responses resulting in gut homeostasis. Given the beneficial role of probiotics, this contribution aims to review the current properties of bovine and human Lf and their derivatives in in vitro probiotic growth and Lf interplay with microbiota described in the piglet model. By using Lf as a component in pharmacological products, we may enable novel strategies that promote probiotic growth while conferring antimicrobial activity against multidrug-resistant microorganisms that cause life-threatening diseases, especially in neonates.

Probiotics and the prevention of necrotizing enterocolitis

BACKGROUND

Immaturity of the host immune system and alterations in the intestinal microbiome appear to be key factors in the pathogenesis of necrotizing enterocolitis (NEC). The aim of this paper is to weigh the evidence for the use of probiotics to prevent NEC in premature infants.

METHODS

Animal studies, randomized controlled trials, observational cohort studies and meta-analyses involving administration of probiotic products for the prevention of NEC were reviewed. This review of the evidence summarizes the available preclinical and clinical data.

RESULTS

In animal models probiotic microbes alter the intestinal microbiome, decrease inflammation and intestinal permeability and decrease the incidence and severity of experimental NEC. In randomized, placebo-controlled trials and cohort studies of premature infants, probiotic microbes decrease the risk of NEC, death and sepsis.

CONCLUSION

Evidence is strong for the prevention of NEC with the use of combination probiotics in premature infants who receive breast milk. The potential risks and benefits of probiotic administration to premature infants should be carefully reviewed with parents.

TYPE OF STUDY

Therapeutic.

LEVEL OF EVIDENCE

I.

Colonization of preterm gnotobiotic piglets with probiotic Lactobacillus rhamnosus GG and its interference with Salmonella Typhimurium

A balanced microbiota of the gastrointestinal tract (GIT) is a prerequisite for a healthy host. The GIT microbiota in preterm infants is determined by the method of delivery and nutrition. Probiotics can improve the GIT microbiota balance and suitable animal models are required to verify their harmlessness. Preterm gnotobiotic piglets were colonized with Lactobacillus rhamnosus GG (LGG) to evaluate its safety and possible protective action against infection with an enteric pathogen, Salmonella Typhimurium (ST). Clinical signs (anorexia, somnolence, fever and diarrhea), bacterial interference and translocation, intestinal histopathology, transcriptions of claudin-1, occludin and interferon (IFN)-γ, intestinal and systemic protein levels of interleukin (IL)-8, IL-12/23 p40 and IFN-γ were compared among (i) germ-free, (ii) LGG-colonized, (iii) ST-infected and (iv) LGG-colonized and subsequently ST-infected piglets for 24 h. Both LGG and ST-colonized the GIT; LGG translocated in some cases into mesenteric lymph nodes and the spleen but did not cause bacteremia and clinical changes. ST caused clinical signs of gastroenteritis, translocated into mesenteric lymph nodes, the spleen, liver and blood, increased claudin-1 and IFN-γ transcriptions, but decreased occludin transcription and increased local and systemic levels of IL-8 and IL-12/23 p40. Previous colonization with LGG reduced ST colonization in the jejunum and translocation into the liver, spleen and blood. It partially ameliorated histopathological changes in the intestine, reduced IL-8 levels in the jejunum and plasma and IL-12/23 p40 in the jejunum. The preterm gnotobiotic piglet model of the vulnerable preterm immunocompromised infant is useful to verify the safety of probiotics and evaluate their protective effect.