ABSTRACT
The gut-lung axis refers to the internal relationship and interaction between the gastrointestinal tract and the respiratory tract at multiple levels.Studies have found that gut microbiota may be closely related to the occurrence and progression of bronchopulmonary dysplasia(BPD)in preterm infants through the gut-lung axis.Studying the mechanism of the interaction between them will help us to extend new therapeutic targets and directions from the perspective of microecology for BPD infants.This article reviews the correlation between gut microbiota and BPD, and the research progress of the mechanism of the gut-lung axis in premature BPD from the aspects of insulin-like growth factor 1, metabolomics, immune regulation, direct transfer, and nutrition.It provides new research ideas for the prevention and treatment of BPD.
ABSTRACT
Objective: To investigate whether batyl alcohol (BTA) can improve the pathology of bronchopulmonary dysplasia (BPD) in newborn rats induced by lipopolysaccharide (LPS) and the mechanism. Methods: Pregnant SD rats (16.5 d) were randomly assigned into Saline group, LPS group, and LPS+BTA group. Amniocentesis injection of LPS was performed to establish neonatal bronchopulmonary dysplasia (BPD) rat model. In LPS+BTA group, LPS and BTA were injected at the same time. After birth, LPS+BTA group was injected with BTA continuously everyday for 7 days. The other two groups were injected with normal saline of equal volume. Lung tissues of neonatal rats on the first, third and seventh day after birth were stained by hematoxylin-eosin (H-E) and resorcin-fuchsin respectively, to observe alveolarization arrest. The mRNA and protein levels of interleukin 1β (IL-1β) in newborn rats lungs were detected by real-time PCR and ELISA. In vitro, mouse macrophages RAW264.7 were cultured to detect IL-1β mRNA levels and protein levels after treatment with LPS and BTA. SD rat bone marrow macrophages were isolated and treated with LPS and BTA. RNA-sequence was taken to screen for possible targets of BTA inhibition of inflammation. Results: The results of H-E staining showed that LPS+BTA group had a milder pathology of BPD, with more secondary septa counts, more alveolar counts, and smaller mean linear intercept (all P<0.05); after BTA intervention the expression levels of IL-1β mRNA and protein in lung tissues of neonatal rats were significantly lower than those in LPS group (both P<0.05). In vitro, IL-1β mRNA and protein increased after LPS stimulation (both P=0.000), but decreased in the LPS+BTA group (both P<0.05). RNA-sequence results showed that BTA inhibited the expressions of some inflammatory factors, such as thrombospondin1 (Thbs1), triggering receptor expressed on myeloid cells 1 (Trem1), and cluster of differentiation 274 (Cd274), and promoted the expressions of some anti-inflammatory factors, such as complement C1q C chain (C1qc), RT1 class Ⅱ, locus Da (RT1-Da), and RT1 class Ⅱ, locus Db1 (RT1-Db1). Conclusion: BTA can improve lung pathology of neonatal rats with BPD by downregulating the expression of IL-1β and reducing inflammatory response.
ABSTRACT
PURPOSE: This report attempts to reveal the incidence and prevalence of bronchopulmonary dysplasia (BPD) and compare the severity according to preceding causes of BPD in very low birth weight (VLBW) infants. METHOD: Retrospective study was done on 293 VLBW infants who were born and admitted to neonatal intensive care unit in Samsung medical center between October, 1995 and December, 2001. Classical BPD was defined as oxygen dependency at 36 week's postmenstrual age (PMA). Ogawa BPD was defined as oxygen dependency at 28 days after birth, with respiratory distress symptoms and the change on chest X-ray finding. This classification further classified as BPD into 5 subtypes by the presence of respiratory distress syndrome (RDS), pathologic chorioamnionitis and the type of chest X-ray finding. BPD by Jobe and Bancalari was defined as oxygen dependency at 28 days after birth and classified as 3 subtypes (severe, moderate, mild) by the severity of oxygen dependency. Comparisons were made among classifications. RESULTS: Classical BPD infants were 56 (19.1%), Ogawa BPD infants were 76 (25.9 %), BPD by Jobe and Bancalari infants were 124 (42.3%). In Ogawa classification, Infants with RDS and the change on chest X-ray were 58 infants (76.4%). There was no statistical difference of mortality between each type of Ogawa BPD. In classification by Jobe and Bancalari, 35 infants (28.2%) belonged to severe BPD and 75 infants (60.5%) belonged to mild BPD. The mortality was highest in severe BPD infants but there was no statistical difference after correction by birth weight. There was no statistical correlation between Ogawa classification and classification by Jobe and Bancalari. CONCLUSION: There was no statistical difference in mortality or severity between each subtype of classifications according to the severity or preceding cause of BPD in very low birth weight infants.
Subject(s)
Female , Humans , Infant , Infant, Newborn , Pregnancy , Birth Weight , Bronchopulmonary Dysplasia , Chorioamnionitis , Classification , Incidence , Infant, Very Low Birth Weight , Intensive Care, Neonatal , Mortality , Oxygen , Parturition , Prevalence , Retrospective Studies , ThoraxABSTRACT
PURPOSE: To see if a similar relationship exists between the decreased number of circulating neutrophils and the development of bronchopulmonary dysplasia (BPD) in preterm infants, we tried to test the hypothesis that claims that preterm infants, who develop BPD, have decreased number of circulating neutrophils than those who do not develop BPD. METHODS: A retrospective cohort study was conducted in 167 preterm infants from August 1995 to July 1997, who were admitted in the neonatal intensive care unit (NICU) of Seoul National University Children's Hospital. RESULTS: BPD was diagnosed in 16% (27/167) of preterm infants. We compared the clinical characteristics of the study population according to the presence or absence of BPD. Compared to non-BPD group, the BPD group had a lower gestational age (29.4 +/- 2.7weeks versus 32.7 +/- 1.7 weeks), lower birth weight (1,240 +/- 486g versus 1,780 +/- 420g), lower incidence of prenatal steroid use (2/27 versus 41/140), decreased number of circulating neutrophils (3,622 +/- 4,866/microliter versus 7,586 +/- 4,545/microliter) at 1 day of life. After adjusting for the variables of the above risk factors, neutropenia (<2,500/microliter) in the peripheral blood increased the odds ratio of developing BPD (OR : 46.3, 95% CI : 17.3-117.2). CONCLUSION: Early postnatal neutropenia might be an important risk factor for the development of BPD and lung injury responsible for the development of BPD might begin at the early postnatal period.
Subject(s)
Humans , Infant, Newborn , Birth Weight , Bronchopulmonary Dysplasia , Cohort Studies , Gestational Age , Incidence , Infant, Premature , Intensive Care, Neonatal , Lung Injury , Neutropenia , Neutrophils , Odds Ratio , Retrospective Studies , Risk Factors , SeoulABSTRACT
PURPOSE: To see if a similar relationship exists between the decreased number of circulating neutrophils and the development of bronchopulmonary dysplasia (BPD) in preterm infants, we tried to test the hypothesis that claims that preterm infants, who develop BPD, have decreased number of circulating neutrophils than those who do not develop BPD. METHODS: A retrospective cohort study was conducted in 167 preterm infants from August 1995 to July 1997, who were admitted in the neonatal intensive care unit (NICU) of Seoul National University Children's Hospital. RESULTS: BPD was diagnosed in 16% (27/167) of preterm infants. We compared the clinical characteristics of the study population according to the presence or absence of BPD. Compared to non-BPD group, the BPD group had a lower gestational age (29.4 +/- 2.7weeks versus 32.7 +/- 1.7 weeks), lower birth weight (1,240 +/- 486g versus 1,780 +/- 420g), lower incidence of prenatal steroid use (2/27 versus 41/140), decreased number of circulating neutrophils (3,622 +/- 4,866/microliter versus 7,586 +/- 4,545/microliter) at 1 day of life. After adjusting for the variables of the above risk factors, neutropenia (<2,500/microliter) in the peripheral blood increased the odds ratio of developing BPD (OR : 46.3, 95% CI : 17.3-117.2). CONCLUSION: Early postnatal neutropenia might be an important risk factor for the development of BPD and lung injury responsible for the development of BPD might begin at the early postnatal period.