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Impact of asymmetric intrauterine growth restriction on organ function in newborn piglets
Reinhard Bauer1, Bernd Walter, Peter Brust
1Institute for Pathophysiology, Friedrich Schiller University, D-07740 Jena, Germany. rbau@mti-n.mti.uni-jena.de
Insights
Asymmetric intrauterine growth restriction (aIUGR) in newborns can accelerate muscle and brain development but may impair kidney function, leading to hypertension and renal failure. Understanding these dual effects is crucial for neonatal care.
Area of Science:
- Neonatal physiology
- Developmental biology
- Comparative pathology
Background:
- Fetal malnutrition can cause asymmetric intrauterine growth restriction (aIUGR), leading to long-term health issues in newborns.
- Understanding organ-specific effects of aIUGR is vital for effective neonatal treatment and management.
- Animal models are essential for elucidating the complex pathogenetic mechanisms of aIUGR.
Purpose of the Study:
- To survey organ-specific structural and functional alterations in newborns affected by aIUGR.
- To investigate the impact of aIUGR on the neonatal response to compromising conditions.
- To demonstrate the utility of animal models in studying aIUGR.
Main Methods:
- Utilized a pig model exhibiting spontaneous runting to study asymmetric intrauterine growth restriction (aIUGR).
- Examined organ-specific changes in newborns with aIUGR.
- Assessed physiological responses to hypoxic and hypotensive conditions.
Main Results:
- Accelerated development observed in skeletal muscles (type I fiber conversion) and brain dopaminergic activity.
- Improved tolerance to gradual oxygen deficit, evidenced by maintained renal blood flow during hypoxia.
- Enhanced cerebrovascular autoregulation during hemorrhagic hypotension.
- Detrimental effects include reduced nephron number, impaired renal excretory function, arterial hypertension, and chronic renal failure.
Conclusions:
- Asymmetric intrauterine growth restriction (aIUGR) presents a complex profile of both beneficial and detrimental effects on neonatal development and organ function.
- aIUGR can enhance resilience to certain physiological stressors like hypoxia and hypotension.
- However, aIUGR significantly compromises renal development and function, predisposing newborns to hypertension and chronic kidney disease.
Abstract:
Fetal malnutrition may induce asymmetric intrauterine growth restriction (aIUGR) with long-lasting consequences. Understanding the organ-specific structural and functional effects aIUGR may have on the newborn, and understanding the potential impact on the neonatal response to compromising conditions, appears to be essential for adequate treatment. Therefore, a survey is given of some organ-specific alterations in newborns, which have suffered from aIUGR. We studied these effects in a model of asymmetric intrauterine growth restriction based on the spontaneous occurrence of runting in pigs. We wish to demonstrate that experimental studies in animal models are necessary and helpful to elucidate pathogenetic mechanisms. aIUGR seems to have both beneficial and detrimental effects on the newborn. The development of skeletal muscles (conversion to oxidative type I fibers) and of their vascular supply as well as of the brain dopaminergic activity is accelerated. Also, aIUGR apparently improves the ability to withstand critical periods of gradual oxygen deficit as shown by the maintenance of renal blood flow during severe systemic hypoxia, and by improved cerebrovascular autoregulation in hemorrhagic hypotension. On the other hand, aIUGR leads to the reduction of the number of nephrons and to impaired renal excretory functions with arterial hypertension and chronic renal failure.
