Metabolic analysis of infants with bronchopulmonary dysplasia under early nutrition therapy: An observational cohort study

Identification of serum metabolite biomarkers in premature infants with bronchopulmonary dysplasia: protocol for a multicentre prospective observational cohort study

INTRODUCTION

Bronchopulmonary dysplasia (BPD) is one of the most common and significant complications of preterm birth. It ultimately leads to a decrease in the quality of life for preterm infants and impacts their long-term health. Early prediction and timely intervention are crucial to halting the development of BPD. This study aims to identify the biomarkers that can predict the early occurrence and development of BPD by screening serum metabolites in preterm infants. This will provide strong support for the early prediction of BPD and targeted interventions in future research.

METHODS AND ANALYSIS

This is a prospective, multicentre, open-label, observational cohort study spanning 3 years. It will be conducted in six major neonatal intensive care units in Shenzhen, China, involving preterm infants born at gestational ages <32 weeks. Demographic data and treatment information will be collected prospectively. Serum samples will be collected at five distinct time points: within 24 hours after birth, at 1 week, 2 weeks, 28 days and at 36 weeks postmenstrual age. These samples will undergo analysis using liquid chromatography-tandem mass spectrometry for untargeted metabolomics studies. Participants will be categorised into BPD and non-BPD groups based on their final diagnosis, and metabolite differences between these groups will be analysed. The study aims to enrol 1500 preterm infants with gestational ages <32 weeks over 3 years. A three-step analysis strategy-discovery, validation and clinical testing-will be used to identify and validate the clinical utility of novel biomarkers. Additionally, a nested case-control study will be conducted, matching participants 1:1 with a control group sharing similar BPD risk factors.

ETHICS AND DISSEMINATION

Our protocol has been approved by the Medical Ethics Committees of all participating hospitals, including Peking University Shenzhen Hospital, Shenzhen People's Hospital, Shenzhen Baoan Women's and Children's Hospital, Longgang District Maternity and Child Healthcare Hospital, Nanshan Maternity and Child Healthcare Hospital and Shenzhen Luohu People's Hospital. We will disseminate our study results through academic conferences and peer-reviewed public journals.

TRIAL REGISTRATION NUMBER

ChiCTR2400081615.

Analysis of variable metabolites in preterm infants with bronchopulmonary dysplasia: a systematic review and meta-analysis

Numerous studies have attempted to identify potential biomarkers for early detection of bronchopulmonary dysplasia (BPD) in preterm infants using metabolomics techniques. However, the presence of consistent evidence remains elusive. Our study aimed to conduct a systematic review and meta-analysis to identify differences in small-molecule metabolites between BPD and non-BPD preterm infants. Through meticulous screening of numerous samples, we identified promising candidates, providing valuable insights for future research. We searched PubMed, the Cochrane Library, Embase, Web of Science, China National Knowledge Internet, Wan-fang database, Chinese Science and Technique Journal Database and Chinese Biomedical Literature Database from inception until January 16, 2024. Studies were comprehensively reviewed against inclusion criteria. We included case-control studies and adhered to Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Study quality was assessed with the Newcastle-Ottawa scale. We compared the changes in metabolite levels between the BPD and non-BPD preterm infants. A meta-analysis was conducted on targeted metabolomics research data based on the strategy of standardized mean differences (MD) and 95% confidence intervals (CI).Fifteen studies (1357 participants) were included. These clinical-based metabolomics studies clarified 110 differential metabolites between BPD and non-BPD preterm infants. The meta-analysis revealed higher glutamate concentration in the BPD group compared to the non-BPD group (MD = 1, 95% CI 0.59 to 1.41, p < 0.00001). Amino acids were identified as the key metabolites distinguishing preterm infants with and without BPD, with glutamate potentially serving as a BPD predictor in this population.

The association between VEGF genetic variations and the risk of bronchopulmonary dysplasia in premature infants: a meta-analysis and systematic review

Objective

Previous studies on the link between VEGF gene polymorphisms and bronchopulmonary dysplasia (BPD) have yielded inconsistent results. This meta-analysis sought to clarify the relationship between genetic variations in the VEGF gene and the risk of BPD.

Methods

Data were collected from multiple databases, including PubMed, Scopus, EMBASE, and CNKI, up to January 5, 2024.

Results

Nineteen case-control studies were analyzed, featuring 1,051 BPD cases and 1,726 healthy neonates. The analysis included four studies on the -460T/C polymorphism (312 cases, 536 controls), four on the -2578C/A polymorphism (155 cases, 279 controls), six on the +405G/C polymorphism (329 cases, 385 controls), and five on the +936C/T polymorphism (225 cases, 526 controls). The meta-analysis suggests that the -460T/C polymorphism may protect against BPD (C vs. T: OR = 0.715, 95% CI 0.543-0.941, p = 0.017; CC vs. TT: OR = 0.478, 95% CI 0.233-0.983, p = 0.045; CC vs. CT + TT: OR = 0.435, 95% CI 0.248-0.764, p = 0.004). No significant associations were found between the -2578C/A, +405G/C, and +936C/T polymorphisms and BPD susceptibility.

Conclusions

This meta-analysis indicates that the C allele of the -460T/C polymorphism may offer protection against BPD. No significant associations were observed for the -2578C/A, +405G/C, and +936C/T polymorphisms.

Emerging role of metabolic reprogramming in hyperoxia-associated neonatal diseases

Oxygen therapy is common during the neonatal period to improve survival, but it can increase the risk of oxygen toxicity. Hyperoxia can damage multiple organs and systems in newborns, commonly causing lung conditions such as bronchopulmonary dysplasia and pulmonary hypertension, as well as damage to other organs, including the brain, gut, and eyes. These conditions are collectively referred to as newborn oxygen radical disease to indicate the multi-system damage caused by hyperoxia. Hyperoxia can also lead to changes in metabolic pathways and the production of abnormal metabolites through a process called metabolic reprogramming. Currently, some studies have analyzed the mechanism of metabolic reprogramming induced by hyperoxia. The focus has been on mitochondrial oxidative stress, mitochondrial dynamics, and multi-organ interactions, such as the lung-gut, lung-brain, and brain-gut axes. In this article, we provide an overview of the major metabolic pathway changes reported in hyperoxia-associated neonatal diseases and explore the potential mechanisms of metabolic reprogramming. Metabolic reprogramming induced by hyperoxia can cause multi-organ metabolic disorders in newborns, including abnormal glucose, lipid, and amino acid metabolism. Moreover, abnormal metabolites may predict the occurrence of disease, suggesting their potential as therapeutic targets. Although the mechanism of metabolic reprogramming caused by hyperoxia requires further elucidation, mitochondria and the gut-lung-brain axis may play a key role in metabolic reprogramming.

The value of hematocrit for predicting bronchopulmonary dysplasia in very low birth weight preterm infants

To determine hematocrit (HCT) and to identify independent risk factors for predicting bronchopulmonary dysplasia (BPD) in preterm infants with very low birth weight (VLBW) infants. This retrospective study included 296 premature infants with VLBW in the neonatal intensive care unit of the First Affiliated Hospital of the University of Science and Technology of China between January 2015 and December 2019. Maternal pregnant information and clinical information as well as hematological parameters of preterm babies were collected and compared. Then the maximum area under the curve of receiver operating characteristic curve was developed to estimate the predictive indicator in the blood. Finally, differential variables together with the predictive index were screened for multiple logistic regression analysis to determine independent prognostic factors for BPD. Infants were divided into a BPD group (134 cases) and a non-BPD group (162 cases). The area under the curve of HCT at postnatal 1 week was 0.737 with the sensitivity of 52.30 % and the specificity of 86.00%. Birth weight (BW) <1.12 kg, gestational age <28.4 weeks, newborn respiratory distress syndrome, mechanical ventilation ≥ 7 days, ventilation associated pneumonia, patent arterial duct, PaO2/FiO2 <300 mm Hg and HCT <0.455 at postnatal 1 week were risk factors for BPD of VLBW infants. HCT levels below 0.455 at 1 week after birth serve as a valuable indicator for the potential development of BPD.

Pharmacometabolomics Profiling of Preterm Infants Validates Patterns of Metabolism Associated With Response to Dexamethasone Treatment for Bronchopulmonary Dysplasia

Bronchopulmonary dysplasia (BPD) is one of the most common health complications of premature birth. Corticosteroids are commonly used for treatment of BPD, but their use is challenging due to variability in treatment response. Previous pharmacometabolomics study has established patterns of metabolite levels with response to dexamethasone. We obtained additional patient samples for metabolomics analysis to find associations between the metabolome and dexamethasone response in a validation cohort. A total of 14 infants provided 15 plasma and 12 urine samples. The measure of treatment response was the calculated change in respiratory severity score (deltaRSS) from pre-to-post treatment. Each metabolite was assessed with paired analysis of pre and post-treatment samples using Wilcoxon signed rank test. Correlation analysis was conducted between deltaRSS and pre-to-post change in metabolite level. Paired association analysis identified 20 plasma and 26 urine metabolites with significant level difference comparing pre to post treatment samples (p < 0.05). 4 plasma and 4 urine metabolites were also significant in the original study. Pre-to-post treatment change in metabolite analysis identified 4 plasma and 8 urine metabolites significantly associated with deltaRSS (p < 0.05). Change in urine citrulline levels showed a similar correlation pattern with deltaRSS in the first study, with increasing level associated with improved drug response. These results help validate the first major findings from pharmacometabolomics of BPD including key metabolites within the urea cycle and trans-4-hydroxyproline as a potential marker for lung injury. Ultimately, this study furthers our understanding of the mechanisms of steroid response in BPD patients and helps to design future targeted metabolomics studies in this patient population.