Effect of Enteral Lipid Supplement on Severe Retinopathy of Prematurity: A Randomized Clinical Trial

Effect of enteral supplementation of DHA with or without ARA in preterm infants: a meta-analysis

OBJECTIVE

This study aimed to assess whether additional enteral docosahexaenoic acid (DHA) supplementation, with or without arachidonic acid (ARA), influences morbidities diagnosed in the neonatal intensive care unit among preterm infants, excluding administration via formula or parenteral nutrition.

DESIGN AND SETTING

This meta-analysis involved a comprehensive search of the PubMed, Embase, Web of Science and Cochrane Library databases from their inception to 9 June 2024.

PATIENTS AND INTERVENTIONS

Randomised controlled trials focusing on the effects of enteral DHA with or without ARA in preterm infants born at ≤34 weeks gestational age or a birth weight ≤2000 g were included.

MAIN OUTCOMES AND MEASURES

The main outcomes included in-hospital mortality, bronchopulmonary dysplasia (BPD), retinopathy of prematurity (ROP), necrotising enterocolitis (NEC), sepsis, intraventricular haemorrhage (IVH) and periventricular leukomalacia (PVL).

RESULTS

Eleven trials evaluating distinct adverse outcomes in preterm infants were incorporated. Of these, nine trials assessing enteral DHA supplementation with or without ARA indicated an increased risk of BPD with a relative risk of 1.11 (95% CI 1.00 to 1.22). Additionally, five trials assessing DHA supplementation without ARA showed an increased risk of BPD with a relative risk of 1.15 (95% CI 1.03 to 1.28). No significant effects were observed on the incidence of ROP, NEC, sepsis, IVH, PVL or in-hospital mortality.

CONCLUSIONS AND RELEVANCE

Enteral supplementation of DHA with or without ARA did not demonstrate protective effects against major complications in preterm infants and even increased the risk of BPD. Further research is warranted to evaluate the necessity of DHA and ARA supplementation in this population.

PROSPERO REGISTRATION NUMBER

CRD42024552578.

Parenteral nutrition for preterm infants: benefits and risks in 2025

Parenteral nutrition (PN) has been a key component of neonatal care for preterm infants since the 1980's and provides macronutrients for growth, along with electrolytes, minerals, vitamins and trace elements. In this article we consider common issues with routine provision to very preterm infants including estimation of nutrient requirements, optimal starting doses of PN, rates of increase and maximum intakes. We consider monitoring strategies and outline common complications which may be serious and fatal. Finally, we consider risk-benefit ratios in different populations of preterm infants, and outline some of the major uncertainties in current practice.

High-dose docosahexaenoic acid for bronchopulmonary dysplasia severity in very preterm infants: a collaborative individual participant data meta-analysis

BACKGROUND

Neonatal supplementation with high-dose docosahexaenoic acid (DHA) omega-3 may benefit neurodevelopment in very preterm infants, but concerns remain regarding a potential increased risk and severity of bronchopulmonary dysplasia (BPD). However, the interpretation of evidence on the effect of DHA on severe BPD is challenging because of the heterogeneity in the BPD definitions used across trials.

OBJECTIVES

This study aims to determine whether, compared with placebo, neonatal enteral supplementation with high-dose DHA, mimicking placental transfer, is associated with severe BPD in very preterm infants using an individual participant data meta-analysis of randomized controlled trials (RCTs).

METHODS

RCTs were eligible if recently conducted in infants born with gestational age (GA) <29 wk and compared enteral supplementation with high-dose DHA alone with a placebo. Using a harmonized data set, the primary outcome of severe BPD was defined as the need for "high-flow" nasal cannula >2 L/min, noninvasive positive airway pressure, or invasive mechanical ventilation at 36 wk postmenstrual age. Secondary outcomes (N = 15) included death, "death or severe BPD," ordinal BPD severity grade, and common neonatal morbidities. Associations between high-dose DHA and outcomes were estimated using a one-stage meta-analysis approach.

RESULTS

Two RCTs were identified in a systematic review (searched up to August 1, 2022; N = 2304) that met inclusion criteria (N = 1801; 904 DHA and 897 placebo; GA 26.7 ± 1.5 wk). Severe BPD in survivors occurred in 290/843 (34.4%) infants in the DHA group and 268/841 (31.9%) infants in the placebo group {relative risk [RR], 1.06 [95% confidence interval (CI): 0.93, 1.21]; P = 0.36}. DHA was not associated with "death or severe BPD" [RR, 1.05 (95% CI: 0.94, 1.17); P = 0.41], the ordinal severity grade [odds ratio for a more severe grade, 1.20 (95% CI: 0.998, 1.45); P = 0.053], or other neonatal outcomes. There was limited evidence of heterogeneity for BPD-related outcomes.

CONCLUSIONS

Neonatal enteral supplementation with high-dose DHA was not significantly associated with severe BPD in very preterm infants.

TRIAL REGISTRATION NUMBER

This study was registered at clinicaltrials.gov as NCT05915806, https://clinicaltrials.gov/study/NCT05915806.

META-ANALYSIS REGISTRY NUMBER AND WEBSITE

PROSPERO, CRD42023431063, https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=431063.

Can prenatal conditions impact the effect of omega-3 on bronchopulmonary dysplasia in very preterm infants? A secondary analysis of a randomized controlled trial

To explore whether prenatal conditions (i.e. chorioamnionitis, preeclampsia or small-for-gestational age (SGA)) affect the very preterm infant's response to docosahexaenoic acid (DHA) on bronchopulmonary dysplasia (BPD), according to mode of delivery, an independent factor shown to modulate this association. Secondary exploratory analysis of the MOBYDIck randomized controlled trial (NCT02371460) evaluating the effect of a neonatal high-dose DHA supplementation through maternal breastmilk compared to placebo. Population was preterm infants born before 29 weeks of gestation in sixteen Canadian neonatal intensive care units. Primary outcome was physiological BPD based on pulse oximetry assessment. Secondary outcomes included "death or BPD"; "moderate-or-severe" BPD; severe BPD; death from any causes. Heterogeneity in the effect of DHA on outcomes was assessed by prenatal conditions and mode of delivery using generalized estimating equation logistic regression models. The trial intended to enroll 800 mothers but was stopped early for safety, likely making subgroup analysis underpowered. 230 mothers (271 infants) were included in DHA group and 226 mothers (252 infants) in placebo group. The association between high-dose DHA and BPD differed by chorioamnionitis status (heterogeneity P=0.04). In infants exposed to chorioamnionitis and vaginal delivery, DHA supplementation was associated with a reduced risk of physiological BPD (adjusted odds ratio, 0.18 [95% CI, 0.05 to 0.62], P=0.007). No heterogeneity was found by maternal preeclampsia (heterogeneity P=0.44) nor SGA status (heterogeneity P=0.17).

CONCLUSION

This secondary analysis generated hypotheses for a potential differential effect of neonatal enteral high-dose DHA supplementation on BPD in very preterm infants according to chorioamnionitis exposure.

WHAT IS KNOWN

• The MOBYDIck trial reported a potential protective effect of docosahexaenoic acid (DHA) supplementation on bronchopulmonary dysplasia (BPD) in infants born vaginally, but not in those born via cesarean section. • Placenta pathologies are associated with inflammation in the infants and could affect the very preterm infant's response to a high-dose DHA supplementation on BPD according to the mode of delivery.

WHAT IS NEW

• This study suggests that, in infants born very preterm before 29 weeks of gestation, the association between enteral high-dose DHA supplementation in neonatal period and BPD at 36 weeks' postmenstrual age differ according to the maternal status for chorioamnionitis at delivery.

Nutrient supplementation mitigates retinal dysfunction in Acox1 knockout mice with impaired peroxisomal fatty acid oxidation

INTRODUCTION

Dyslipidemia contributes to many retinal diseases, but underlying lipid processing pathways are not fully understood. Peroxisomes oxidize very long-chain fatty acids and generate docosahexaenoic acid (DHA). Mutations in peroxisomal genes can result in severe neural retinal dysfunction. However, therapeutic approaches for peroxisomal diseases remain scarce, and dietary strategies yield inconsistent results.

OBJECTIVES

This study sought to elucidate retinal metabolic adaptations resulting from impaired peroxisomal fatty acid oxidation and to evaluate the therapeutic potential of nutrient supplementation in peroxisomal retinal disease.

METHODS

In mice with global knockout (KO) of acyl-coenzyme A oxidase 1 (Acox1), encoding the first and rate-limiting enzyme in peroxisomal fatty acid oxidation, the retina was characterized at postnatal day (P) 30 during development. Retinal thickness, photoreceptor structure, and function were examined. Proteome analysis was utilized for molecular mechanistic investigation. Metabolomics and fatty acid profiling were conducted to study metabolic alterations in the retina. Nutrient intervention was performed to test if providing deficient nutrients could attenuate the observed retinal dysfunction.

RESULTS

In P30 Acox1 KO mice, we observed impaired neural retinal signaling, accompanied by reduced expression of genes involved in phototransduction. Proteomics suggested diminished glucose and mitochondrial metabolism, supported by decreased mitochondrial number and mitochondrial DNA copy number. Metabolomics showed reduced abundance of retinal pyruvate, and pyruvate supplementation from P30-P60 attenuated neural retinal dysfunction in Acox1 KO mice at P60. Furthermore, Acox1 KO mice at P30 exhibited a significant decrease in omega-3 (n-3) fatty acids and a compensatory increase in n-6 fatty acids. Dietary supplementation with DHA (n-3) or DHA plus arachidonic acid (n-6) from P30-P60 mitigated the progression of retinal dysfunction in Acox1 KO mice.

CONCLUSION

Retinal dysfunction, decreased mitochondrial number, and metabolic imbalance were observed in mice with impaired peroxisomal fatty acid oxidation. Nutrient intervention may offer a promising therapeutic approach for peroxisomal diseases.

A review on lipid inclusion in preterm formula: Characteristics, nutritional support, challenges, and future perspectives

The lack of nutrient accumulation during the last trimester and the physiological immaturity at birth make nutrition for preterm infants a significant challenge. Lipids are essential for preterm infant growth, neurodevelopment, immune function, and intestinal health. However, the inclusion of novel lipids in preterm formulas has rarely been discussed. This study discusses specific lipid recommendations for preterm infants according to authoritative legislation based on their physiological characteristics. The gaps in lipid composition, such as fatty acids, triacylglycerols, and complex lipids, between preterm formulas and human milk have been summarized. The focus of this study is mainly on the vital roles of lipids in nutritional support, including long-chain polyunsaturated fatty acids, structural lipids, milk fat global membrane ingredients, and other minor components. These lipids have potential applications in preterm formulas for improving lipid absorption, regulating lipid metabolism, and protecting against intestinal inflammation. The lipidome and microbiome can be used to provide adequately powered evidence of the effects of lipids. This study proposes nutritional strategies for preterm infants and suggests approaches to enhance their lipid quality in preterm formula.

Functional Infant Formula Additives

Breastfeeding is the ideal initial feeding method for providing nutrition to full-term infants and is recommended by major health organizations, including the American Academy of Pediatrics and the World Health Organization. Despite improvements in global breastfeeding rates, many infants still receive formula. Significant advancements have been achieved in the safety and nutritional content of modern formulas. Various functional additives, such as human milk oligosaccharides, milk fat globule membrane, docosahexaenoic acid, and lactoferrin, are used with the aim to replicate some of the benefits of breast milk. These additives enhance formula by providing benefits beyond basic nutrition. The aim of this review is to summarize these additives and their impact on infant nutrition and development.

The evolution of nutritional care in preterm infants with a focus on the extreme preterm infant

The evolution of nutritional care in preterm infants, particularly those classified as extremely preterm, has undergone significant advancements in recent years. These infants, born at less than 28 weeks of gestation, face unique challenges related to their elevated nutrient requirements, underdeveloped organ systems and minimal reserves, posing a need for timely and specialised nutritional strategies. Historically, the nutritional management of preterm infants focussed on short-term goals to promote survival. In recent years, the focus has shifted to the quality of nutrient provision to optimise neurodevelopment and longer-term health outcomes. This review highlights the shift from a generalised nutritional approach to a robust, evidence-based approach for preterm infants, acknowledging the intricate interplay between nutrition, holistic care and developmental outcomes. As neonatal care continues to evolve, ongoing research will refine nutritional interventions, optimise growth and enhance the long-term health outcomes of these vulnerable infants.

Prospective Cohort Study Investigating Polyunsaturated Fatty Acids and Chronic Lung Disease in Preterm Infants

OBJECTIVE

 Chronic lung disease (CLD) is a complication of prematurity. Studies examining the effects of long-chain polyunsaturated fatty acids (LC-PUFAs) on CLD are conflicting. This study investigated LC-PUFAs in the red blood cell membrane (RBCM) in preterm infants.

STUDY DESIGN

 This prospective observational study included infants with gestational age <32 weeks or birth weight <2 kg and at least one LC-PUFA measurement in the first month of life. Subjects without CLD (CON group) were compared with those with CLD (CLD group) and then by CLD severity.

RESULTS

 Seventy infants were included (CON n = 29; CLD n = 41). Twenty-six infants had Grade 1 CLD; 12 had Grade 2 CLD; 3 had Grade 3 CLD. When the CLD group was compared with the CON group, the overall mean (95% confidence interval) RBCM% for linoleic acid (LA) was similar (CLD vs. CON 12.5% [11.7-13.4%] vs. 11.2% [10.2-12.3%], p = 0.06) but the overall mean arachidonic acid (ARA) was lower (17.6% [17.1-18.0%] vs. 18.6% [18.1-19.2%], p < 0.01). During weeks 1 to 4, LA% was similar, while ARA% was lower in weeks 2 and 3 (18.8 ± 2.2% vs. 20.0 ± 1.5%, p = 0.05, 16.8 ± 2.0% vs. 18.3 ± 1.6%, p = 0.01). A similar trend was noted when groups were compared by CLD severity. The CLD group had a higher overall mean α-linolenic acid (ALA) compared with the CON group (0.4% [0.3-0.4%] vs. 0.2% [0.2-0.3%], p < 0.01) but no difference in docosahexaenoic acid (DHA; 3.8% [3.4-4.1%] vs. 3.8% [3.4-4.3%], p = 0.80). During weeks 1 to 4, ALA% was higher during week 1 only (0.4 ± 0.3% vs. 0.2 ± 0.1%, p < 0.01), and DHA% was similar for weeks 1 to 4. Results were similar when groups were compared by CLD severity.

CONCLUSION

 In this study, low ARA status was associated with CLD.

KEY POINTS

· In this study, infants with CLD had a similar RBCM% of LA, but a lower percentage of its downstream LC-PUFA, ARA, compared with infants without CLD.. · In this study, infants with CLD had a higher RBCM% of α-linolenic acid, but a similar percentage of its downstream LC-PUFA, DHA, compared with infants without CLD.. · In this study, these trends were similiar when groups were compared by CLD severity..

Impact of Omega-3 Enriched Lipid Emulsions on Retinopathy of Prematurity in Very Low Birth Weight Infants: A Retrospective Cohort Analysis

OBJECTIVES

To assess the effects of ω-3 long-chain polyunsaturated fatty acid (LCPUFA)-enriched lipid emulsions (SMOFlipid) vs. traditional soybean oil-based lipid emulsions (Intralipid) on the occurrence and severity of retinopathy of prematurity (ROP) in infants with very low birth weight (VLBW).

METHODS

In this retrospective cohort study, 301 VLBW infants who received either SMOFlipid or Intralipid for a minimum of 14 d were included. The main outcome measured was the frequency and severity of ROP, with secondary outcomes covering other complications associated with preterm birth.

RESULTS

Of the infants studied, 180 were administered SMOFlipid, while 121 received Intralipid. The incidence of ROP was notably lower in the SMOFlipid group (32.8% vs. 45.5%; RR 0.59; 95% CI 0.36-0.94; P = 0.026). Additionally, the occurrence of severe ROP was reduced by 66.06% in infants given SMOFlipid (5.6% vs. 16.5%; RR 0.30; 95% CI 0.13-0.66; P = 0.002). Multivariate logistic regression suggested that using SMOFlipid was linked to a reduced risk of both ROP (OR 0.44; 95% CI 0.24-0.82; P = 0.010) and severe ROP (OR 0.09; 95% CI 0.03-0.30; P < 0.001). There were no considerable differences noted in other complications associated with preterm birth between the two groups.

CONCLUSIONS

Compared to Intralipid, SMOFlipid treatment reduced both the risk and severity of ROP. Parenteral supplementation with fish oil-containing emulsions might offer a novel approach to lowering the incidence and severity of ROP in VLBW infants.

PLASMA PROTEOME, METABOLOME MENDELIAN RANDOMIZATION IDENTIFIES SEPSIS THERAPEUTIC TARGETS

ABSTRACT

Background : The interrelation between the plasma proteome and plasma metabolome with sepsis presents a multifaceted dynamic that necessitates further research to elucidate the underlying causal mechanisms. Methods : Our investigation used public genome-wide association study data to explore the relationships among the plasma proteome, metabolome, and sepsis, considering different sepsis subgroup. Initially, two-sample Mendelian randomization established causal connections between the plasma proteome and metabolome with sepsis. Subsequently, multivariate and iterative Mendelian randomization analyses were performed to understand the complex interactions in plasma during sepsis. The validity of these findings was supported by thorough sensitivity analyses. Result : The study identified 25 plasma proteins that enhance risk and 34 that act as protective agents in sepsis. After P value adjustment (0.05/1306), ICAM5 emerged with a positive correlation to sepsis susceptibility ( P value = 2.14E-05, OR = 1.10, 95% CI = 1.05-1.15), with this significance preserved across three sepsis subgroup examined. Additionally, 29 plasma metabolites were recognized as risk factors, and 15 as protective factors for sepsis outcomes. After P value adjustment (0.05/997), elevated levels of 1,2,3-benzenetriol sulfate (2) was significantly associated with increased sepsis risk ( P value = 3.37E-05, OR = 1.18, 95% CI = 1.09-1.28). Further scrutiny revealed that this plasma metabolite notably augments the abundance of ICAM5 protein ( P value = 3.52E-04, OR = 1.11, 95% CI = 1.04-1.17), devoid of any detected heterogeneity, pleiotropy, or reverse causality. Mediated Mendelian randomization revealed ICAM5 mediated 11.9% of 1,2,3-benzenetriol sulfate (2)'s total effect on sepsis progression. Conclusion : This study details the causal link between the plasma proteome and metabolome with sepsis, highlighting the roles of ICAM5 and 1,2,3-benzenetriol sulfate (2) in sepsis progression, both independently and through crosstalk.

Efficacy and Safety of Prophylactic Agents in Prevention of Retinopathy of Prematurity: A Systematic Review and Meta-analysis of Randomised Controlled rials

OBJECTIVE

Retinopathy of prematurity (ROP) is a leading cause of preventable childhood blindness in preterm infants with low birth weight. The efficacy and safety of prophylactic agents, including vitamin A, propranolol and lipids, in reducing ROP incidence remain unclear. This systematic review and meta-analysis evaluated the effectiveness and safety of these agents in preventing ROP.

METHODS AND ANALYSIS

A systematic search was conducted in Embase, MEDLINE and CENTRAL databases. Eight randomised controlled trials involving 1101 preterm infants were included. We assessed the incidence of ROP at any stage, severe ROP, adverse events and mortality. Subgroup analyses were performed for each prophylactic agent. Data were pooled using the inverse variance weighting method and reported as risk ratios (RRs) with 95% CI.

RESULTS

No significant reduction in ROP incidence at any stage was found in the intervention groups compared with placebo (RR=0.83; 95% CI= (0.69 to 1.00); p=0.05; I²=0%). Lipids significantly reduced severe ROP incidence (RR=0.48; 95% CI= (0.28 to 0.80); p=0.005), while vitamin A (RR=1.14; 95% CI= (0.51 to 2.54); p=0.75) and propranolol (RR=0.69; 95% CI= (0.29 to 1.65); p=0.41) did not. There were no significant differences in adverse events (RR=0.83; 95% CI= (0.59 to 1.17); p=0.28) or mortality (RR=0.93; 95% CI= (0.67 to 1.30); p=0.68) across all groups.

CONCLUSION

Lipids show promise in reducing severe ROP in preterm infants, while vitamin A and propranolol were not effective. Further research is needed to confirm these findings and explore the potential role of lipids in clinical practice.

Eicosapentaenoic Acid (EPA) and Docosahexaenoic Acid (DHA): A Targeted Antioxidant Strategy to Counter Oxidative Stress in Retinopathy

Omega-3 fatty acids are critical components of cell membranes, including those in the retina. Specifically, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are the primary omega-3 fatty acids that have been studied for their potential benefits in retinal health, preventing the progression of retinopathy. Several studies have shown that a higher intake of omega-3 fatty acids is associated with a lower risk of developing diabetic retinopathy and age-related macular degeneration (AMD). Reviewing clinical trials and observational studies that support the protective role of omega-3s in retinal disorders is essential. This comprehensive review aims to evaluate the current literature on the role of omega-3 fatty acids, exploring their mechanisms of action and anti-inflammatory, anti-angiogenic, and neuroprotective roles in the retina. Omega-3s have been shown to inhibit abnormal blood vessel growth in the retina, which is a significant factor in proliferative diabetic retinopathy and neovascular AMD. Furthermore, omega-3 fatty acids are often studied with other nutrients, such as lutein, zeaxanthin, and vitamins, for their synergistic effects on retinal health. Reviewing these combinations can help understand how omega-3s can be part of a comprehensive approach to preventing or treating retinopathies, especially in diabetic patients. This review emphasizes the preventive function of EPA and DHA in alleviating oxidative stress-related damage in retinal diseases, concentrating on their antioxidative mechanisms.

Platelet characteristics in extremely preterm infants after fatty acid supplementation: a randomized controlled trial

BACKGROUND

Two risk factors for severe retinopathy of prematurity (ROP) in extremely preterm infants are thrombocytopenia and low levels of arachidonic acid (AA) and docosahexaenoic acid (DHA). To date, these risk factors have not been linked.

METHOD

Infants born < 28 weeks gestational age (GA) from 2016 to 2019 were randomized to postnatal enteral AA/DHA supplementation or standard care (controls). Levels of AA and DHA, platelet counts ( < 100 × 109/L defined as thrombocytopenia) and platelet-related proteins in the infants' first four weeks of life were evaluated for their association with severe ROP.

RESULTS

The mean birthweight of 178 included infants was 806 ± 200 grams, and the mean GA was 25.6 ± 1.4 weeks. During the first four postnatal weeks, 20.2% of AA/DHA-supplemented infants had thrombocytopenia versus 27.7% of controls (p = 0.29). In infants with thrombocytopenia, fewer AA/DHA-supplemented infants developed severe ROP than non-supplemented controls, 29.4% (5/17) versus 65.4% (17/26) (p = 0.031). Thrombocytopenia and serum levels of AA and DHA correlated with several platelet-related proteins involved in angiogenesis and ROP, such as platelet-derived growth factor subunits A and B and vascular endothelial growth factor.

CONCLUSIONS

AA and DHA supplementation is associated with less severe ROP in thrombocytopenic infants, possibly by modulating platelet activation and function.

IMPACT

Postnatal enteral supplementation with arachidonic acid (AA) and docosahexaenoic acid (DHA) to extremely preterm infants reduces the risk of severe retinopathy of prematurity (ROP) in infants with thrombocytopenia. The impact of AA and DHA might be, at least in part, mediated through altered platelet activation. We found that AA and DHA may reduce the risk of severe ROP, possibly by modulating platelet-related proteins involved in angiogenesis. Our findings strongly support that supplementing AA and DHA to extremely preterm infants is crucial and can significantly impact their health.

Survival and characteristics of retinopathy of prematurity in micro-premature infants

OBJECTIVE

To describe the risk and nature of retinopathy of prematurity (ROP) in micro-premature infants (≤26 weeks' gestational age [GA]).

METHODS

Retrospective analysis of prospectively collected data from infants born at 22-26 weeks' GA over a 5-year period.

RESULTS

A total of 502 infants were identified, of whom 414 survived to discharge (82.5%). The Vermont Oxford Network database documented clinical follow-up data and ROP outcomes for all 414 patients; complete ROP clinical records were available for 294 of the infants who survived (70.8%). Forty infants were born between 22 and 23 weeks' GA (group A, 13.6%), and 254 were born between 24 and 26 weeks' GA (group B, 86.4%). Survival for group A infants was worse than that of group B infants (66.2% vs 85.4%; p < 0.01). Survival of group A infants improved during the study period (R2 = 0.625). Overall, 59.9% of infants developed any ROP and 8.5% developed type 1 ROP. Group A infants were more likely to develop ROP (90.0% vs 48.6%; p < 0.01) and type 1 ROP (30.0% vs 5.1%; p < 0.01) than group B infants. Group A infants developed ROP at an earlier age (32 + 6 weeks vs 33 + 3 weeks; p = 0.02) and were more likely to have zone I disease on presentation (65.0% vs 20.5%; p < 0.01), but there was no difference in the corrected gestational age of peak severity of ROP (35 + 2 weeks vs 34 + 5 weeks; p = 0.36).

CONCLUSION

The most premature infants, born at 22-23 weeks' GA, develop ROP at an earlier age, are more likely to present with posterior disease, and have a high risk of disease requiring treatment.

Fetal Red Blood Cells: A Comprehensive Review of Biological Properties and Implications for Neonatal Transfusion

Transfusion guidelines worldwide include recommendations regarding the storage length, irradiation, or even donor cytomegalovirus serostatus of red blood cell (RBC) units for anemic neonates. Nevertheless, it is totally overlooked that RBCs of these patients fundamentally differ from those of older children and adults. These differences vary from size, shape, hemoglobin composition, and oxygen transport to membrane characteristics, cellular metabolism, and lifespan. Due to these profound dissimilarities, repeated transfusions of adult RBCs in neonates deeply modify the physiology of circulating RBC populations. Unsurprisingly, the number of RBC transfusions in preterm neonates, particularly if born before 28 weeks of gestation, predicts morbidity and mortality. This review provides a comprehensive description of the biological properties of fetal, cord blood, and neonatal RBCs, including the implications that neonatal RBCs, and their replacement by adult RBCs, may have for perinatal disease pathophysiology.

Postnatal Dysregulation of Androgens in Extremely Preterm Male Infants

Context

Neurodevelopmental impairments are common among survivors of extremely preterm birth, particularly in males. Hyperactivation of the hypothalamic-pituitary-gonadal (HPG) axis has been suggested as an underlying cause, but this has been poorly investigated.

Objective

Establish levels and temporal changes in circulating androgens in extremely preterm infant males.

Methods

Observational cohort study analyzing cord blood serum (n = 25) and postnatal plasma (n = 13) collected from day 0 until week 11 from infant males born at 22.8-27.9 weeks gestational age. Testosterone and dihydrotestosterone (DHT) were determined using gas chromatography mass spectrometry, sex hormone-binding globulin (SHBG) with an enzyme-linked immunosorbent assay, and follicle-stimulating hormone (FSH) and luteinizing hormone (LH) with the Luminex xMAP multiplex assay.

Results

Testosterone and DHT levels were higher on day 0 (median 4.27 and 0.30 ng/mL) than in cord blood (0.15 and 0.01 ng/mL) (P < .001 for both). Levels of the hormones then declined rapidly until day 5 (median 0.16 and 0.12 ng/mL), then remained relatively constant throughout the study period. Median levels of testosterone and DHT across the whole study period were approximately 6-fold higher than reported in utero levels. FSH and LH showed similar postnatal patterns as the androgens. SHBG steadily increased over time, and, as a result, the fraction of bioavailable testosterone declined with infant postnatal age.

Conclusion

The HPG axis is activated immediately after birth in extremely preterm infant males, resulting in an androgen pulse occurring several months earlier than during a normal pregnancy. The long-term implications of high androgen exposure during a sensitive neurodevelopmental period warrant further studies.

Docosahexaenoic Acid and Sleep Quality in Very and Extreme Preterm Infants

The results regarding the association of plasma docosahexaenoic acid (DHA) levels with sleep duration conflict. This study aimed to investigate the effect of oral administration of DHA on the sleep quality of Brazilian extreme preterm infants. This cohort study is part of the Joinville Docosahexaenoic Acid Study (JoiDHA) conducted with 59 infants in Joinville, Brazil. Sleep quality was assessed using the Brief Infant Sleep Questionnaire, which consists of 12 questions about the quality of sleep the week prior to its application and was answered by the parents/guardians. Of the 59 children who participated in the study, 37 (62.7%) were supplemented with DHA and 22 (37.3%) did not receive DHA. The prevalence of poor sleep quality was higher among children with the weight status at birth <50th percentile (68.2%; p = 0.045) when compared to children ≥50th percentile. However, Poisson regression analysis showed that neither weight status at birth nor DHA use was associated with sleep quality, even after adjusting for the same variables. In summary, sleep quality 12-24 months after birth was not associated with DHA supplementation in very and extreme preterm infants. Additional studies that address the increase in DHA intake would be important for the understanding of the effect of this fatty acid on sleep quality.

Retinopathy of Prematurity in Eight Portuguese Neonatal Intensive Care Units: Incidence, Risk Factors, and Progression-A Prospective Multicenter Study

BACKGROUND/OBJECTIVES

Retinopathy of prematurity (ROP) is a retinal neovascular disease affecting preterm infants. Identifying risk factors for its development and progression is critical for effective screening and prevention. This study aimed to analyze the incidence of ROP and identify key risk factors for its development and progression.

METHODS

We conducted a prospective, observational cohort study on 455 neonates (gestational age [GA] < 32 weeks or birth weight < 1500 g) across eight Portuguese NICUs.

RESULTS

ROP incidence was 37.8%, with 4.6% requiring treatment. Multivariate analysis identified low GA and the number of red blood cell (RBC) transfusions as significant factors for ROP development and progression. After adjusting for these variables, platelet transfusions, high maximum fraction of inspired oxygen (FiO2) in the second week, and surfactant use remained significantly associated with ROP development, while early and late sepsis, maternal chronic hypertension, and delayed enteral nutrition were associated with progression to ROP requiring treatment.

CONCLUSIONS

These findings underscore the importance of addressing low GAs and adult RBC transfusions in ROP risk management and suggest that maximum FiO2, platelet transfusions, and sepsis also play crucial roles. Larger studies are needed to validate these results and explore preventive interventions, particularly regarding the impact of multiple adult RBC transfusions on fetal hemoglobin percentages.

Neurofilament light chain associates with IVH and ROP in extremely preterm infants

BACKGROUND

Neurofilament light chain (NfL) is known for indicating adult brain injury, but the role of NfL in extremely preterm infants is less studied. This study examines the relationship between NfL and neurovascular morbidities in these infants.

METHODS

A secondary analysis of the Mega Donna Mega trial was conducted on preterm infants <28 weeks gestational age (GA). The study measured NfL levels and proteomic profiles related to the blood-brain barrier in serum from birth to term-equivalent age, investigating the association of NfL with GA, retinopathy of prematurity (ROP), intraventricular hemorrhage (IVH), and blood-brain barrier proteins.

RESULTS

Higher NfL levels were seen in the first month in infants with severe IVH and for those born <25 weeks GA (independent of ROP or IVH). Additionally, infants born at 25-27 weeks GA with high NfL were at increased risk of developing severe ROP (independent of IVH). NfL was significantly associated with the proteins CDH5, ITGB1, and JAM-A during the first month.

CONCLUSION

NfL surges after birth in extremely preterm infants, particularly in those with severe IVH and ROP, and in the most immature infants regardless of IVH or ROP severity. These findings suggest NfL as a potential predictor of neonatal morbidities, warranting further validation studies.

IMPACT STATEMENT

This study shows that higher NfL levels are related to neurovascular morbidities in extremely preterm infants. The degree of immaturity seems important as infants born <25 weeks gestational age exhibited high postnatal serum NfL levels irrespective of neurovascular morbidities. Our findings suggest a potential link between NfL and neurovascular morbidities possibly affected by a more permeable blood-brain barrier.

Long-chain polyunsaturated fatty acids supplementation and sepsis: a systematic review and meta-analysis

BACKGROUND

Long chain polyunsaturated fatty acids (LCPUFAs) have proven to be essential for development in preterm infants and have been studied for their capacity to reduce inflammation and infection rates, including sepsis in enteral and parenteral nutrition. The aim of this review and meta-analysis is to gather the information available on this subject to determine if n-3 polyunsaturated fatty acids can reduce sepsis incidence in preterm infants.

METHODS

This systematic review was conducted by searching in the databases MEDLINE (via PubMed), ISI-Web of Science, EMBASE, SCOPUS, SciELO, and Cochrane Library databases. We analyzed the data regarding sepsis using the Grading of Recommendations Assessment, Development and Evaluation approach to assess the quality of the evidence.

RESULTS

A total of 40 trials were included for review and 35 trials had the data available for quantitative analysis. LCPUFAs supplementation did not reduce incidence of sepsis (relative risk (RR), confidence interval (CI) 0.95 [0.87, 1.03] P = 0.87; I2 = 0%). These results remained consistent after the sensitivity analysis.

CONCLUSION

The results of this systematic review and meta-analysis indicate that LCPUFA supplementation is not associated with a significant decrease in the incidence of sepsis in premature infants.

IMPACT

Reviewing the information available about LCPUFA supplementation and sepsis since the results in previous Clinical Trials (CT) are inconclusive. It summarizes the results of 42 CT and we have not found conclusive results regarding sepsis in the literature. It could be of clinical interest for pediatricians and nutritionists.

Structured Triacylglycerol with Optimal Arachidonic Acid and Docosahexaenoic Acid Content for Infant Formula Development: A Bio-Accessibility Study

Polyunsaturated fatty acids (PUFAs), especially arachidonic acid (ARA) and docosahexaenoic acid (DHA), are extremely important fatty acids for brain development in the fetus and early childhood. Premature infants face challenges obtaining these two fatty acids from their mothers. It has been reported that supplementation with triacylglycerols (TAGs) with an ARA:DHA (w/w) ratio of 2:1 may be optimal for preterm infants, as presented in commercial formulas such as Formulaid™. This study explored methods to produce TAGs with a 2:1 ratio (ARA:DHA), particularly at the more bioavailable sn-2 position of the glycerol backbone. Blending and enzymatic acidolysis of microalgae oil (rich in DHA) and ARA-rich oil yielded products with the desired ARA:DHA ratio, enhancing sn-2 composition compared to Formulaid™ (1.6 for blending and 2.3 for acidolysis versus 0.9 in Formulaid™). Optimal acidolysis conditions were 45 °C, a 1:3 substrate molar ratio, 10% Candida antarctica lipase, and 4 h. The process was reproducible, and scalable, and the lipase could be reused. In vitro digestion showed that 75.5% of the final product mixture was bio-accessible, comprising 19.1% monoacylglycerols, ~50% free fatty acids, 14.6% TAGs, and 10.1% diacylglycerols, indicating better bio-accessibility than precursor oils.

Nutritional interventions to prevent retinopathy of prematurity

Very preterm infants are at high risk of growth failure. Poor weight gain is a prominent risk factor for retinopathy of prematurity (ROP) and optimizing nutrition could potentially promote growth and reduce ROP. Most infants at risk of ROP need parenteral nutrition initially and studies of enhanced parenteral provision of lipids and amino acids have suggested a beneficial effect on ROP. Higher amino acid intake was associated with lower incidence of hyperglycemia, a risk factor for ROP. For very preterm infants, providing unpasteurized fortified raw maternal breast milk appears to have a dose-dependent preventive effect on ROP. These infants become deficient in arachidonic acid (ArA) and docosahexaenoic acid (DHA) after birth when the maternal supply is lost. Earlier studies have investigated the impact of omega-3 fatty acids on ROP with mixed results. In a recent study, early enteral supplementation of ArA 100 mg/kg/d and DHA 50 mg/kg/d until term equivalent age reduced the incidence of severe ROP by 50%. IMPACT: Previous reviews of nutritional interventions to prevent morbidities in preterm infants have mainly addressed bronchopulmonary dysplasia, brain lesions and neurodevelopmental outcome. This review focusses on ROP. Neonatal enteral supplementation with arachidonic acid and docosahexaenoic acid, at levels similar to the fetal accretion rate, has been found to reduce severe ROP by 50% in randomized controlled trials.

Oral DHA supplementation and retinopathy of prematurity: the Joinville DHA Clinical Trial

Retinopathy of prematurity (ROP) is a leading cause of blindness in premature infants. The condition is associated with DHA deficiency. This study aimed to investigate the effect of DHA supplementation on the occurrence of ROP in infants receiving oral oil drops. It is part of the Joinville DHA study, a non-parallel-group cohort study conducted from March 2020 to January 2023 at a public maternity hospital in Brazil. Infants born before 33 weeks of gestational age or with a birth weight ≤ 1500 g were recruited. Among 155 infants, 81 did not receive and 74 received DHA supplementation until complete vascularisation of the peripheral retina. There was a higher incidence of infants with ROP in the unsupplemented group (58·6 %) compared with the DHA group (41·4 %), but this difference was NS (P = 0·22). Unadjusted logistic regression analysis showed that patent ductus arteriosus and neonatal corticosteroids were significantly (P < 0·05) associated with ROP in both groups. In the DHA group, surfactant use was also associated with ROP (P = 0·003). After adjusting for important covariates, patent ductus arteriosus and neonatal corticosteroids continued to be significant for infants in the unsupplemented group (OR = 3·99; P = 0·022 and OR = 5·64; P = 0·019, respectively). In the DHA group, only surfactant use continued to be associated with ROP (OR = 4·84; P = 0·015). In summary, DHA supplementation was not associated with ROP. Further studies are necessary to better understand the relationship between DHA supplementation, ROP and associated comorbidities.

Maternal n-3 enriched diet reprograms the offspring neurovascular transcriptome and blunts inflammation induced by endotoxin in the neonate

Infection during the perinatal period can adversely affect brain development, predispose infants to ischemic stroke and have lifelong consequences. We previously demonstrated that diet enriched in n-3 polyunsaturated fatty acids (n-3 PUFA) transforms brain lipid composition in the offspring and protects the neonatal brain from stroke, in part by blunting injurious immune responses. Critical to the interface between the brain and systemic circulation is the vasculature, endothelial cells in particular, that support brain homeostasis and provide a barrier to systemic infection. Here, we examined whether maternal PUFA-enriched diets exert reprograming of endothelial cell signalling in postnatal day 9 mice after modeling aspects of infection using LPS. Transcriptome analysis was performed on microvessels isolated from brains of pups from dams maintained on 3 different maternal diets from gestation day 1: standard, n-3 enriched or n-6 enriched diets. Depending on the diet, in endothelial cells LPS produced distinct regulation of pathways related to immune response, cell cycle, extracellular matrix, and angiogenesis. N-3 PUFA diet enabled higher immune reactivity in brain vasculature, while preventing imbalance of cell cycle regulation and extracellular matrix cascades that accompanied inflammatory response in standard diet. Cytokine analysis revealed a blunted LPS response in blood and brain of offspring from dams on n-3 enriched diet. Analysis of cerebral vasculature in offspring in vivo revealed no differences in vessel density. However, vessel complexity was decreased in response to LPS at 72 h in standard and n-6 diets. Thus, LPS modulates specific transcriptomic changes in brain vessels of offspring rather than major structural vessel characteristics during early life. N-3 PUFA-enriched maternal diet in part prevents an imbalance in homeostatic processes, alters inflammation and ultimately mitigates changes to the complexity of surface vessel networks that result from infection. Importantly, maternal diet may presage offspring neurovascular outcomes later in life.

Natural Products in the Treatment of Retinopathy of Prematurity: Exploring Therapeutic Potentials

Retinopathy of prematurity (ROP) is a vascular disorder affecting the retinas of preterm infants. This condition arises when preterm infants in incubators are exposed to high oxygen levels, leading to oxidative stress, inflammatory responses, and a downregulation of vascular endothelial growth factors, which causes the loss of retinal microvascular capillaries. Upon returning to room air, the upregulation of vascular growth factors results in abnormal vascular growth of retinal endothelial cells. Without appropriate intervention, ROP can progress to blindness. The prevalence of ROP has risen, making it a significant cause of childhood blindness. Current treatments, such as laser therapy and various pharmacologic approaches, are limited by their potential for severe adverse effects. Therefore, a deeper understanding of ROP's pathophysiology and the development of innovative treatments are imperative. Natural products from plants, fungi, bacteria, and marine organisms have shown promise in treating various diseases and have gained attention in ROP research due to their minimal side effects and wide-ranging beneficial properties. This review discusses the roles and mechanisms of natural products that hold potential as therapeutic agents in ROP management.

Epithelial Membrane Protein 2 (EMP2) Blockade Attenuates Pathological Neovascularization in Murine Oxygen-Induced Retinopathy

Purpose

Retinopathy of prematurity (ROP) results from postnatal hyperoxia exposure in premature infants and is characterized by aberrant neovascularization of retinal blood vessels. Epithelial membrane protein-2 (EMP2) regulates hypoxia-inducible factor (HIF)-induced vascular endothelial growth factor (VEGF) production in the ARPE-19 cell line and genetic knock-out of Emp2 in a murine oxygen-induced retinopathy (OIR) model attenuates neovascularization. We hypothesize that EMP2 blockade via intravitreal injection protects against neovascularization.

Methods

Ex vivo choroid sprouting assay was performed, comparing media and human IgG controls versus anti-EMP2 antibody (Ab) treatment. In vivo, eyes from wild-type (WT) mice exposed to hyperoxia from postnatal (P) days 7 to 12 were treated with P12 intravitreal injections of control IgG or anti-EMP2 Abs. Neovascularization was assessed at P17 by flat mount imaging. Local and systemic effects of anti-EMP2 Ab treatment were assessed.

Results

Choroid sprouts treated with 30 µg/mL of anti-EMP2 Ab demonstrated a 48% reduction in vessel growth compared to control IgG-treated sprouts. Compared to IgG-treated controls, WT OIR mice treated with 4 µg/g of intravitreal anti-EMP2 Ab demonstrated a 42% reduction in neovascularization. They demonstrated down-regulation of retinal gene expression in pathways related to vasculature development and up-regulation in genes related to fatty acid oxidation and tricarboxylic acid cycle respiratory electron transport, compared to controls. Anti-EMP2 Ab-treated OIR mice did not exhibit gross retinal histologic abnormalities, vision transduction abnormalities, or weight loss.

Conclusions

Our results suggest that EMP2 blockade could be a local and specific treatment modality for retinal neovascularization in oxygen-induced retinopathies, without systemic adverse effects.

A promising case of preclinical-clinical translation: β-adrenoceptor blockade from the oxygen-induced retinopathy model to retinopathy of prematurity

Although compartmentalization of the eye seems to promote its experimental manipulation, drug penetration to its posterior part is severely limited by hard barriers thus hindering drug development for eye diseases. In particular, angiogenesis-related retinal diseases share common mechanisms and are responsible for the majority of cases of blindness. Their prevalence is globally increasing mostly because of the increased incidence of systemic pathologies in the adult. Despite the number of preclinical findings demonstrating the efficacy of novel treatments, therapy of retinal neovascular diseases still remains confined to intravitreal anti-vascular endothelial growth factor treatments with some extension to anti-inflammatory therapy. In the mare magnum of preclinical findings aimed to develop novel avenues for future therapies, most compounds, despite their efficacy in experimental models, do not seem to meet the criteria for their therapeutic application. In particular, the groove between preclinical findings and their clinical application increases instead of decreasing and the attempt to bridging the gap between them creates intense frustration and a sense of defeat. In this complex scenario, we will discuss here the role that overactivation of the sympathetic system plays in retinal vessel proliferation in response to hypoxia using the oxygen-induced retinopathy (OIR) model. The potential application of the beta-adrenoceptor (β-AR) blockade with propranolol to the treatment of retinopathy of prematurity will be also discussed in light of preclinical findings in the OIR model and clinical trials using propranolol in preterm infants either per os or as eye drops.

ROP: 80 Years after Its Detection - Where Do We Stand and How Long Will We Continue to Laser?

BACKGROUND

Retinopathy of prematurity (ROP), a potentially blinding disease, is increasing worldwide because of the increased survival of extremely preterm and preterm infants born where oxygen monitoring and ROP screening programs are insufficient. Repeated retinal examinations are stressful for infants, and laser photocoagulation treatment for sight-threatening ROP is destructive. The use of anti-VEGF agents instead of lasers is widespread but requires a long-term follow-up because of late recurrence of the disease. In addition, the optimal anti-VEGF agent dosage and long-term systemic effects require further study.

SUMMARY

Interventions preventing ROP would be far preferable, and systemic interventions might promote better development of the brain and other organs. Interventions such as improved oxygen control, provision of fresh maternal milk, supplementation with arachidonic acid and docosahexaenoic acid, and fetal hemoglobin preservation by reducing blood sample volumes may help prevent ROP and reduce the need for treatment. Free readily available online tools to predict severe ROP may reduce unnecessary eye examinations and select, for screening, those at a high risk of needing treatment.

KEY MESSAGES

Treatment warranting ROP is a sign of impaired neurovascular development in the central nervous system. Preventative measures to improve the outcomes are available. Screening can be refined using tools that can predict severe ROP. Laser treatment and anti-VEGF agents are valuable treatment modalities that may complement each other in recurrent ROP.

Therapeutic Effects of Anti-Inflammatory and Anti-Oxidant Nutritional Supplementation in Retinal Ischemic Diseases

Appropriate nutrients are essential for cellular function. Dietary components can alter the risk of systemic metabolic diseases, including cardiovascular diseases, cancer, diabetes, and obesity, and can also affect retinal diseases, including age-related macular degeneration, diabetic retinopathy, and glaucoma. Dietary nutrients have been assessed for the prevention or treatment of retinal ischemic diseases and the diseases of aging. In this article, we review clinical and experimental evidence concerning the potential of some nutritional supplements to prevent or treat retinal ischemic diseases and provide further insights into the therapeutic effects of nutritional supplementation on retinopathies. We will review the roles of nutrients in preventing or protecting against retinal ischemic diseases.

Arachidonic acid and docosahexaenoic acid levels correlate with the inflammation proteome in extremely preterm infants

BACKGROUND & AIM

Clinical trials supplementing the long-chain polyunsaturated fatty acids (LCPUFAs) docosahexaenoic acid (DHA) and arachidonic acid (AA) to preterm infants have shown positive effects on inflammation-related morbidities, but the molecular mechanisms underlying these effects are not fully elucidated. This study aimed to determine associations between DHA, AA, and inflammation-related proteins during the neonatal period in extremely preterm infants.

METHODS

A retrospective exploratory study of infants (n = 183) born below 28 weeks gestation from the Mega Donna Mega trial, a randomized multicenter trial designed to study the effect of DHA and AA on retinopathy of prematurity. Serial serum samples were collected after birth until postnatal day 100 (median 7 samples per infant) and analyzed for phospholipid fatty acids and proteins using targeted proteomics covering 538 proteins. Associations over time between LCPUFAs and proteins were explored using mixed effect modeling with splines, including an interaction term for time, and adjusted for gestational age, sex, and center.

RESULTS

On postnatal day one, 55 proteins correlated with DHA levels and 10 proteins with AA levels. Five proteins were related to both fatty acids, all with a positive correlation. Over the first 100 days after birth, we identified 57 proteins to be associated with DHA and/or AA. Of these proteins, 41 (72%) related to inflammation. Thirty-eight proteins were associated with both fatty acids and the overall direction of association did not differ between DHA and AA, indicating that both LCPUFAs similarly contribute to up- and down-regulation of the preterm neonate inflammatory proteome. Primary examples of this were the inflammation-modulating cytokines IL-6 and CCL7, both being negatively related to levels of DHA and AA in the postnatal period.

CONCLUSIONS

This study supports postnatal non-antagonistic and potentially synergistic effects of DHA and AA on the inflammation proteome in preterm infants, indicating that supplementation with both fatty acids may contribute to limiting the disease burden in this vulnerable population.

CLINICAL REGISTRATION NUMBER

ClinicalTrials.gov (NCT03201588).

Evidence on docosahexaenoic acid and arachidonic acid supplementation for preterm infants

PURPOSE OF REVIEW

For many decades, docosahexaenoic acid (DHA) supplementation was tested in premature infants to achieve an intake equivalent to the average level in breast milk, but this approach has led to conflicting results in terms of development and health outcomes. Higher doses of DHA closer to fetal accumulation may be needed.

RECENT FINDINGS

The efficacy of DHA supplementation for preterm infants at a dose equivalent to the estimated fetal accumulation rate is still under investigation, but this may be a promising approach, especially in conjunction with arachidonic acid supplementation. Current data suggest benefit for some outcomes, such as brain maturation, long-term cognitive function, and the prevention of retinopathy of prematurity. The possibility that supplementation with highly unsaturated oils increases the risk of neonatal morbidities should not be ruled out, but current meta-analyzes do not support a significant risk.

SUMMARY

The published literature supports a DHA intake in preterm infants that is closer to the fetal accumulation rate than the average breast milk content. Supplementation with DHA at this level in combination with arachidonic acid is currently being investigated and appears promising.

Targeting adenosine A2A receptors for early intervention of retinopathy of prematurity

Retinopathy of prematurity (ROP) continues to pose a significant threat to the vision of numerous children worldwide, primarily owing to the increased survival rates of premature infants. The pathologies of ROP are mainly linked to impaired vascularization as a result of hyperoxia, leading to subsequent neovascularization. Existing treatments, including anti-vascular endothelial growth factor (VEGF) therapies, have thus far been limited to addressing pathological angiogenesis at advanced ROP stages, inevitably leading to adverse side effects. Intervention to promote physiological angiogenesis during the initial stages could hold the potential to prevent ROP. Adenosine A2A receptors (A2AR) have been identified in various ocular cell types, exhibiting distinct densities and functionally intricate connections with oxygen metabolism. In this review, we discuss experimental evidence that strongly underscores the pivotal role of A2AR in ROP. In particular, A2AR blockade may represent an effective treatment strategy, mitigating retinal vascular loss by reversing hyperoxia-mediated cellular proliferation inhibition and curtailing hypoxia-mediated neovascularization in oxygen-induced retinopathy (OIR). These effects stem from the interplay of endothelium, neuronal and glial cells, and novel molecular pathways (notably promoting TGF-β signaling) at the hyperoxia phase. We propose that pharmacological targeting of A2AR signaling may confer an early intervention for ROP with distinct therapeutic benefits and mechanisms than the anti-VEGF therapy.

Enteral supplementation with arachidonic and docosahexaenoic acid and pulmonary outcome in extremely preterm infants

Enteral supplementation with arachidonic acid (AA) and docosahexaenoic acid (DHA) in extremely preterm infants has shown beneficial effects on retinopathy of prematurity and pulmonary outcome whereas exclusive DHA supplementation has been associated with increased pulmonary morbidity. This secondary analysis evaluates pulmonary outcome in 204 extremely preterm infants, randomized to receive AA (100 mg/kg/day) and DHA (50 mg/kg/day) enterally from birth until term age or standard care. Pulmonary morbidity was primarily assessed based on severity of bronchopulmonary dysplasia (BPD). Serum levels of AA and DHA during the first 28 days were analysed in relation to BPD. Supplementation with AA:DHA was not associated with increased BPD severity, adjusted OR 1.48 (95 % CI 0.85-2.61), nor with increased need for respiratory support at post menstrual age 36 weeks or duration of oxygen supplementation. Every 1 % increase in AA was associated with a reduction of BPD severity, adjusted OR 0.73 (95 % CI 0.58-0.92). In conclusion, in this study, with limited statistical power, enteral supplementation with AA:DHA was not associated with an increased risk of pulmonary morbidity, but higher levels of AA were associated with less severe BPD. Whether AA or the combination of AA and DHA have beneficial roles in the immature lung needs further research.

Retinopathy of Prematurity-Targeting Hypoxic and Redox Signaling Pathways

Retinopathy of prematurity (ROP) is a proliferative vascular ailment affecting the retina. It is the main risk factor for visual impairment and blindness in infants and young children worldwide. If left undiagnosed and untreated, it can progress to retinal detachment and severe visual impairment. Geographical variations in ROP epidemiology have emerged over recent decades, attributable to differing levels of care provided to preterm infants across countries and regions. Our understanding of the causes of ROP, screening, diagnosis, treatment, and associated risk factors continues to advance. This review article aims to present the pathophysiological mechanisms of ROP, including its treatment. Specifically, it delves into the latest cutting-edge treatment approaches targeting hypoxia and redox signaling pathways for this condition.

Arachidonic and docosahexaenoic acid supplementation and brain maturation in preterm infants; a double blind RCT

BACKGROUND

Arachidonic acid (ARA) and docosahexaenoic acid (DHA) are important structural components of neural cellular membranes and possess anti-inflammatory properties. Very preterm infants are deprived of the enhanced placental supply of these fatty acids, but the benefit of postnatal supplementation on brain development is uncertain. The aim of this study was to test the hypothesis that early enteral supplementation with ARA and DHA in preterm infants improves white matter (WM) microstructure assessed by diffusion-weighted MRI at term equivalent age.

METHODS

In this double-blind, randomized controlled trial, infants born before 29 weeks gestational age were allocated to either 100 mg/kg ARA and 50 mg/kg DHA (ARA:DHA group) or medium chain triglycerides (control). Supplements were started on the second day of life and provided until 36 weeks postmenstrual age. The primary outcome was brain maturation assessed by diffusion tensor imaging (DTI) using Tract-Based Spatial Statistics (TBSS) analysis.

RESULTS

We included 120 infants (60 per group) in the trial; mean (range) gestational age was 26+3 (22+6 - 28+6) weeks and postmenstrual age at scan was 41+3 (39+1 - 47+0) weeks. Ninety-two infants underwent MRI imaging, and of these, 90 had successful T1/T2 weighted MR images and 74 had DTI data of acceptable quality. TBSS did not show significant differences in mean or axial diffusivity between the groups, but demonstrated significantly higher fractional anisotropy in several large WM tracts in the ARA:DHA group, including corpus callosum, the anterior and posterior limb of the internal capsula, inferior occipitofrontal fasciculus, uncinate fasciculus, and the inferior longitudinal fasciculus. Radial diffusivity was also significantly lower in several of the same WM tracts in the ARA:DHA group.

CONCLUSION

This study suggests that supplementation with ARA and DHA at doses matching estimated fetal accretion rates improves WM maturation compared to control treatment, but further studies are needed to ascertain any functional benefit.

CLINICAL TRIAL REGISTRATION

www.

CLINICALTRIALS

gov; ID:NCT03555019.

Effect of arachidonic and docosahexaenoic acid supplementation on quality of growth in preterm infants: A secondary analysis of a randomized controlled trial

BACKGROUND & AIMS

A balanced supply of arachidonic acid (ARA) and docosahexaenoic acid (DHA) may be crucial for quality of growth in preterm infants. This secondary analysis of a randomized controlled trial aimed to determine the effect of enhanced ARA and DHA supplementation on growth and body composition in infants born before 29 weeks of gestation. Furthermore, we aimed to study associations between human milk feeding, growth patterns and body composition.

METHODS

The ImNuT-trial randomized 121 infants to receive a daily supplement with medium chain triglycerides (control) or 100 mg/kg ARA and 50 mg/kg DHA (ARA:DHA group) from the second day of life until 36 weeks postmenstrual age. Growth and body composition were evaluated up to 3 months corrected age.

RESULTS

The ARA:DHA group showed better linear growth from birth to term equivalent age compared to the control group; mean difference in z score change from birth for length was 0.74 ([95% CI, 0.17-1.3]; p = 0.010). There were no differences in growth and body composition outcomes at 3 months corrected age between the groups. An increase in z score for weight after 36 weeks postmenstrual age and breastfeeding at 3 months corrected age were the strongest positive predictors of fat mass% at 3 months corrected age (both, p < 0.001).

CONCLUSION

Early enhanced supplementation of ARA and DHA may be beneficial with respect to somatic growth in very preterm infants.

CLINICAL TRIAL REGISTRATION

The trial has been registered on www.

CLINICALTRIALS

gov, ID: NCT03555019.

Oxidative stress in the eye and its role in the pathophysiology of ocular diseases

Oxidative stress occurs through an imbalance between the generation of reactive oxygen species (ROS) and the antioxidant defense mechanisms of cells. The eye is particularly exposed to oxidative stress because of its permanent exposure to light and due to several structures having high metabolic activities. The anterior part of the eye is highly exposed to ultraviolet (UV) radiation and possesses a complex antioxidant defense system to protect the retina from UV radiation. The posterior part of the eye exhibits high metabolic rates and oxygen consumption leading subsequently to a high production rate of ROS. Furthermore, inflammation, aging, genetic factors, and environmental pollution, are all elements promoting ROS generation and impairing antioxidant defense mechanisms and thereby representing risk factors leading to oxidative stress. An abnormal redox status was shown to be involved in the pathophysiology of various ocular diseases in the anterior and posterior segment of the eye. In this review, we aim to summarize the mechanisms of oxidative stress in ocular diseases to provide an updated understanding on the pathogenesis of common diseases affecting the ocular surface, the lens, the retina, and the optic nerve. Moreover, we discuss potential therapeutic approaches aimed at reducing oxidative stress in this context.

Postnatal hyperglycemia alters amino acid profile in retinas (model of Phase I ROP)

Nutritional deprivation occurring in most preterm infants postnatally can induce hyperglycemia, a significant and independent risk factor for suppressing physiological retinal vascularization (Phase I retinopathy of prematurity (ROP)), leading to compensatory but pathological neovascularization. Amino acid supplementation reduces retinal neovascularization in mice. Little is known about amino acid contribution to Phase I ROP. In mice modeling hyperglycemia-associated Phase I ROP, we found significant changes in retinal amino acids (including most decreased L-leucine, L-isoleucine, and L-valine). Parenteral L-isoleucine suppressed physiological retinal vascularization. In premature infants, severe ROP was associated with a higher mean intake of parenteral versus enteral amino acids in the first two weeks of life after adjustment for treatment group, gestational age at birth, birth weight, and sex. The number of days with parenteral amino acids support independently predicted severe ROP. Further understanding and modulating amino acids may help improve nutritional intervention and prevent Phase I ROP.

Retinopathy of prematurity: from oxygen management to molecular manipulation

INTRODUCTION

Retinopathy of prematurity (ROP) is a vasoproliferative disorder of the premature retina with the potential to progress to extraretinal neovascularisation. This review serves as an introduction to retinopathy of prematurity (ROP), outlining key parts of ROP pathophysiology, diagnosis and treatment. ROP is traditionally diagnosed by indirect ophthalmoscopy and classified using anatomical zones, stages of disease, and the presence or absence of "plus disease" (dilation and tortuosity of the major retinal arterioles and venules). ROP has a bi-phasic pathophysiology: initial hyperoxia causes reduced retinal vascularisation, followed by pathological vaso-proliferation resulting from subsequent hypoxia and driven by vascular endothelial growth factor (VEGF).

ADVANCEMENTS IN MANAGEMENT

This review summarises previous trials to establish optimum oxygen exposure levels in newborns and more recently the development of anti-VEGF agents locally delivered to block pathological neovascularisation, which is technically easier to administer and less destructive than laser treatment.

FUTURE DIRECTIONS

There remains an ongoing concern regarding the potential unwanted systemic effects of intravitreally administered anti-VEGF on the overall development of the premature baby. Ongoing dosing studies may lessen these fears by identifying the minimally effective dose required to block extraretinal neovascularisation.

Pathophysiology of Retinopathy of Prematurity

Retinopathy of prematurity (ROP) is a complex disease involving development of the neural retina, ocular circulations, and other organ systems of the premature infant. The external stresses of the ex utero environment also influence the pathophysiology of ROP through interactions among retinal neural, vascular, and glial cells. There is variability among individual infants and presentations of the disease throughout the world, making ROP challenging to study. The methods used include representative animal models, cell culture, and clinical studies. This article describes the impact of maternal-fetal interactions; stresses that the preterm infant experiences; and biologic pathways of interest, including growth factor effects and cell-cell interactions, on the complex pathophysiology of ROP phenotypes in developed and emerging countries.

Visual outcome at 2.5 years of age in ω-3 and ω-6 long-chain polyunsaturated fatty acid supplemented preterm infants: a follow-up of a randomized controlled trial

Background

We investigated ophthalmological outcomes at 2.5 years of corrected age in children born extremely preterm (EPT) to evaluate the effects of postnatal enteral supplementation with ω-3 and ω-6 long-chain polyunsaturated fatty acids.

Methods

In the Mega Donna Mega clinical trial, EPT infants born at less than 28 weeks of gestation were randomized to receive an enteral supplementation of docosahexaenoic acid (DHA) and arachidonic acid (AA) from birth to 40 weeks postmenstrual age. In this exploratory follow-up at 2.5 years of corrected age, we assessed visual acuity (VA), refraction, manifest strabismus, and nystagmus. Satisfactory VA was defined as ≥20/63. Multiple imputation (MI) was used to address the issue of missing data.

Findings

Of 178 children in the trial, 115 (with median gestational age (GA) of 25 + 4/7 weeks and median birth weights of 790 g) were ophthalmologically assessed at a median corrected age of 2.7 years (range 2.0-3.9 years). VA assessment was missing in 42.1% (75/178), in 41.7% (35/84) of the AA/DHA supplemented infants, and in 42.6% (40/94) of the control infants. After MI and adjustments for GA, study center, plurality, and corrected age at VA exam, no significant effect of AA/DHA supplementation was detected in VA outcome (≥20/63) (odds ratio 2.16, confidence interval 95% 0.99-4.69, p = 0.053).

Interpretation

In this randomized controlled trial follow-up, postnatal supplementation with enteral AA/DHA to EPT children did not significantly alter VA at 2.5 years of corrected age. Due to the high loss to follow-up rate and the limited statistical power, additional studies are needed.

Funding

The Swedish Medical Research Council #2020-01092, The Gothenburg Medical Society, Government grants under the ALF agreement ALFGBG-717971 and ALFGBG-971188, De Blindas Vänner, Knut and Alice Wallenberg Foundation - Wallenberg Clinical Scholars, NIHEY017017, EY030904BCHIDDRC (1U54HD090255 Massachusetts Lions Eye Foundation) supported the study.

The development of blood protein profiles in extremely preterm infants follows a stereotypic evolution pattern

BACKGROUND

Preterm birth is the leading cause of neonatal mortality and morbidity. Early diagnosis and interventions are critical to improving the clinical outcomes of extremely premature infants. Blood protein profiling during the first months of life in preterm infants can shed light on the role of early extrauterine development and provide an increased understanding of maturation after extremely preterm birth and the underlying mechanisms of prematurity-related disorders.

METHODS

We have investigated the blood protein profiles during the first months of life in preterm infants on the role of early extrauterine development. The blood protein levels were analyzed using next generation blood profiling on 1335 serum samples, collected longitudinally at nine time points from birth to full-term from 182 extremely preterm infants.

RESULTS

The protein analysis reveals evident predestined serum evolution patterns common for all included infants. The majority of the variations in blood protein expression are associated with the postnatal age of the preterm infants rather than any other factors. There is a uniform protein pattern on postnatal day 1 and after 30 weeks postmenstrual age (PMA), independent of gestational age (GA). However, during the first month of life, GA had a significant impact on protein variability.

CONCLUSIONS

The unified pattern of protein development for all included infants suggests an age-dependent stereotypic development of blood proteins after birth. This knowledge should be considered in neonatal settings and might alter the clinical approach within neonatology, where PMA is today the most dominant age variable.

Retinopathy of Prematurity: The Role of Nutrition

Retinopathy of prematurity (ROP) is a leading cause of childhood blindness. ROP occurs in infants who are born very preterm. In ROP, retinal blood vessel development, which is prematurely arrested in preterm infants, is altered by perinatal exposures like oxygen and inflammation. Optimizing nutritional practices for preterm infants may mitigate the risk of ROP. In this article, we review the evidence that postnatal growth, hyperglycemia, polyunsaturated fatty acids, and breast milk provision may affect ROP risk. We also outline the current management strategies for ROP and describe the vision outcomes of children affected by ROP. [Pediatr Ann. 2023;52(8):e303-e308.].

Dietary Implications of Polyunsaturated Fatty Acids during Pregnancy and in Neonates

Certain limitations exist for animals to modify fatty acid changes. Besides the role of arachidonic acid (AA), docosahexaenoic acid (DHA) and other 20-carbon long-chain polyunsaturated fatty acids (LCPUFAs) for the synthesis of inflammatory mediators as eicosanoids, different LCPUFAs have many other effects, including their abilities to regulate gene expression and downstream events. LCPUFAs are susceptible to autoxidation, which is prevented by the action of antioxidants in the form of enzymes like superoxide dismutases, catalases and peroxidases, as well as antioxidant compounds that protect against oxidation or repair the damage caused. Under normal conditions, the fetus needs both essential fatty acids (EFAs) and LCPUFAs, which are obtained from its mother by placental transfer. In early pregnancy, dietary derived fatty acids are accumulated in maternal adipose tissue. However, during late pregnancy, corresponding to the period of the highest fetal growth, maternal adipose tissue becomes catabolic and LCPUFAs are released into the circulation by adipose lipolytic activity. The released LCPUFAs are taken up by maternal liver to be esterified and released back to the circulation as triacylglycerides (TAGs) in very-low-density lipoprotein (VLDL) that become available to the placenta to be transferred to the fetus in the form of non-esterified fatty acids (NEFAs). An enhanced adipose tissue lipolysis is maintained around parturition and esterified LCPUFAs are diverted to mammary glands thanks to an increased activity of lipoprotein lipase for milk production. Throughout this process, LCPUFAs become available to the newborn during suckling. The important role of both DHA and AA for the development of the nervous system and for growth has motivated their dietary supplement during different postnatal stages. This has been especially important in preterm infants both because under normal conditions, the fetus acquires most of these fatty acids during late pregnancy, and because the immaturity of the enzyme systems for the synthesis of AA and DHA from their respective EFAs.

Proteomics identifies lipocalin-2 in neonatal inflammation associated with cerebrovascular alteration in mice and preterm infants

Staphylococcus (S.) epidermidis is the most common nosocomial coagulase-negative staphylococci infection in preterm infants. Clinical signs of infection are often unspecific and novel markers to complement diagnosis are needed. We investigated proteomic alterations in mouse brain after S. epidermidis infection and in preterm infant blood. We identified lipocalin-2 (LCN2) as a crucial protein associated with cerebrovascular changes and astrocyte reactivity in mice. We further proved that LCN2 protein expression was associated with endothelial cells but not astrocyte reactivity. By combining network analysis and differential expression approaches, we identified LCN2 linked to blood C-reactive protein levels in preterm infants born <28 weeks of gestation. Blood LCN2 levels were associated with similar alterations of cytokines and chemokines in both infected mice and human preterm infants with increased levels of C-reactive protein. This experimental and clinical study suggests that LCN2 may be a marker of preterm infection/inflammation associated with cerebrovascular changes and neuroinflammation.

Pharmacotherapy and Nutritional Supplements for Neovascular Eye Diseases

In this review, we aim to provide an overview of the recent findings about the treatment of neovascular retinal diseases. The use of conventional drugs and nutraceuticals endowed with antioxidant and anti-inflammatory properties that may support conventional therapies will be considered, with the final aim of achieving risk reduction (prevention) and outcome improvement (cooperation between treatments) of such sight-threatening proliferative retinopathies. For this purpose, we consider a medicinal product one that contains well-defined compound(s) with proven pharmacological and therapeutic effects, usually given for the treatment of full-blown diseases. Rarely are prescription drugs given for preventive purposes. A dietary supplement refers to a compound (often an extract or a mixture) used in the prevention or co-adjuvant treatment of a given pathology. However, it must be kept in mind that drug-supplement interactions may exist and might affect the efficacy of certain drug treatments. Moreover, the distinction between medicinal products and dietary supplements is not always straightforward. For instance, melatonin is formulated as a medicinal product for the treatment of sleep and behavioral problems; at low doses (usually below 1 mg), it is considered a nutraceutical, while at higher doses, it is sold as a psychotropic drug. Despite their lower status with respect to drugs, increasing evidence supports the notion of the beneficial effects of dietary supplements on proliferative retinopathies, a major cause of vision loss in the elderly. Therefore, we believe that, on a patient-by-patient basis, the administration of nutraceuticals, either alone or in association, could benefit many patients, delaying the progression of their disease and likely improving the efficacy of pharmaceutical drugs.

Key biologically active components of breast milk and their beneficial effects

Maternal breast milk is the penultimate nutritional source for term and preterm neonates. Its composition is highly complex and includes multiple factors that enhance the development of nearly every neonatal organ system leading to both short- and long-term health benefits. Intensive research is focused on identifying breast milk components that enhance infant health. However, this research is complicated by the significant impact of maternal factors and the processing of pumped breast milk on bioactive ingredients. Optimizing enteral nutrition is particularly important for preterm neonates who miss the transplacental acquisition of nutrients in the third trimester of pregnancy and are at risk for illnesses associated with gut barrier dysfunction, including sepsis and necrotizing enterocolitis. In this review, we will discuss the health benefits of breast milk and its bioactive components.

Retinopathy of prematurity: risk stratification by gestational age

OBJECTIVE

To identify gestational age (GA) specific risk factors for severe ROP (sROP).

STUDY DESIGN

Single-center cohort stratified by GA into <24 weeks, 24-26 weeks and ≥27 weeks.

RESULTS

132/1106 (11.9%) developed sROP. Time to full feeds was the only risk factor [HR 1.003 (1.001-1.006), p = 0.04] for infants<24 weeks GA. For infants 24-26 weeks GA, a higher GA was protective [HR 0.66 (0.51-0.85), p < 0.01], whereas steroids for bronchopulmonary dysplasia (BPD) [HR 2.21 (1.28-3.26), p < 0.01], patent ductus arteriosus (PDA) ligation [HR 1.99 (1.25-3.11), p < 0.01] and use of nitric oxide [HR 1.96 (1.11-3.30), p = 0.01] increased the hazard of sROP. Increasing birthweight was protective [HR 0.70 (0.54-0.89), p < 0.01] in infants ≥27 weeks GA. Cumulative hazard of sROP reached 1.0 by fifteen weeks for <24 weeks GA, 0.4 by twenty weeks for 24-26 weeks GA, and 0.05 by twenty weeks after birth for ≥27 weeks GA.

CONCLUSIONS

Risk factors, cumulative hazard, and time to sROP vary by GA.

Modification of serum fatty acids in preterm infants by parenteral lipids and enteral docosahexaenoic acid/arachidonic acid: A secondary analysis of the Mega Donna Mega trial

BACKGROUND & AIM

Preterm infants risk deficits of long-chain polyunsaturated fatty acids (LCPUFAs) that may contribute to morbidities and hamper neurodevelopment. We aimed to determine longitudinal serum fatty acid profiles in preterm infants and how the profiles are affected by enteral and parenteral lipid sources.

METHODS

Cohort study analyzing fatty acid data from the Mega Donna Mega study, a randomized control trial with infants born <28 weeks of gestation (n = 204) receiving standard nutrition or daily enteral lipid supplementation with arachidonic acid (AA):docosahexaenoic acid (DHA) (100:50 mg/kg/day). Infants received an intravenous lipid emulsion containing olive oil:soybean oil (4:1). Infants were followed from birth to postmenstrual age 40 weeks. Levels of 31 different fatty acids from serum phospholipids were determined by GC-MS and reported in relative (mol%) and absolute concentration (μmol l-1) units.

RESULTS

Higher parenteral lipid administration resulted in lower serum proportion of AA and DHA relative to other fatty acids during the first 13 weeks of life (p < 0.001 for the 25th vs the 75th percentile). The enteral AA:DHA supplement increased the target fatty acids with little impact on other fatty acids. The absolute concentration of total phospholipid fatty acids changed rapidly in the first weeks of life, peaking at day 3, median (Q1-Q3) 4452 (3645-5466) μmol l-1, and was positively correlated to the intake of parenteral lipids. Overall, infants displayed common fatty acid trajectories over the study period. However, remarkable differences in fatty acid patterns were observed depending on whether levels were expressed in relative or absolute units. For example, the relative levels of many LCPUFAs, including DHA and AA, declined rapidly after birth while their absolute concentrations increased in the first week of life. For DHA, absolute levels were significantly higher compared to cord blood from day 1 until postnatal week 16 (p < 0.001). For AA, absolute postnatal levels were lower compared to cord blood from week 4 throughout the study period (p < 0.05).

CONCLUSIONS

Our data show that parenteral lipids aggravate the postnatal loss of LCPUFAs seen in preterm infants and that serum AA available for accretion is below that in utero. Further research is needed to establish optimal postnatal fatty acid supplementation and profiles in extremely preterm infants to promote development and long-term health.

CLINICAL TRIAL REGISTRY

ClinicalTrials.gov, identifier: NCT03201588.