Related Experiment Video
Updated: Jun 27, 2026
Development of a Neonatal Piglet Acute Lung Injury Model Recreating the Early Environment of Preterm Infant Lungs
Published on: October 31, 2025
Studies of meconium-induced lung injury: inflammatory cytokine expression and apoptosis
1Division of Neonatology, Department of Pediatrics, The University of Illinois at Chicago, Chicago, IL 60517, USA. dsagar@uic.edu
Abstract:
To review current literature related to cellular mechanisms of meconium-induced lung injury (MILI). Review of published experimental in vitro and in vivo MAS studies using human and animal lung cells. We found that meconium induces expression of cytokines and angiotensin II (ANG II)-induced apoptotic process in the lung cells. We postulate that inflammatory cytokines induce ANG II expression, which causes apoptotic cell death after binding to its AT1 receptors. We also demonstrated expression of serpins associated with meconium instillation into the lungs. Serpins are proteins that inhibit cellular proteases and elastases. Expression of serpins may be an attempt to recover lung from these injurious effects. In summary our studies show that whereas meconium induces inflammatory cytokines and subsequent cell apoptosis, the lung cells also try to protect themselves by inducing serpins. The balance of these interactions will determine the residual damage. We believe these new findings are very important in understanding of MILI.
Insights
Meconium exposure triggers lung cell apoptosis via cytokines and angiotensin II (ANG II). Lung cells counteract this injury by producing serpins, proteins that inhibit proteases, influencing residual lung damage.
Area of Science:
- Pulmonary Medicine
- Cellular Biology
- Pathophysiology
Background:
- Meconium aspiration syndrome (MAS) is a significant cause of neonatal respiratory distress.
- The precise cellular mechanisms underlying meconium-induced lung injury (MILI) require further elucidation.
Purpose of the Study:
- To review and synthesize current literature on the cellular mechanisms of MILI.
- To understand the molecular pathways involved in meconium-induced lung cell damage and repair.
Main Methods:
- Comprehensive review of published experimental in vitro and in vivo studies.
- Analysis of studies utilizing human and animal lung cells exposed to meconium.
Main Results:
- Meconium induces the expression of inflammatory cytokines and angiotensin II (ANG II) in lung cells.
- ANG II, via AT1 receptors, mediates meconium-induced apoptotic cell death.
- Meconium instillation upregulates serpin expression, suggesting a protective cellular response.
Conclusions:
- MILI involves a complex interplay between pro-inflammatory and pro-apoptotic pathways (cytokines, ANG II) and endogenous protective mechanisms (serpins).
- The balance between injury and repair pathways dictates the extent of residual lung damage in MILI.
- Understanding these cellular interactions is crucial for developing targeted therapies for MILI.
