Early Life Injury Alters Spinal Astrocyte Development
Judy J Yoo1,2, Elizabeth K Serafin2, J Matthew Kofron3,4
1Medical Scientist Training Program and Neuroscience Graduate Program, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267.
Summary
Neonatal injury disrupts spinal astrocyte development, impacting pain signaling. Early life pain alters astrocyte structure and gene expression, with sex-dependent effects on microglial interactions.
Area of Science:
- Neuroscience
- Developmental Biology
- Pain Research
Background:
- Neonatal injury affects spinal cord synaptic transmission and pain pathways.
- Astrocytes are crucial for synapse development and pain maintenance.
- The impact of early life injury on spinal astrocyte maturation remains largely unknown.
Purpose of the Study:
- To investigate how neonatal injury affects the postnatal development and maturation of spinal astrocytes in the superficial dorsal horn (SDH).
- To characterize the structural and transcriptomic changes in SDH astrocytes following early life pain.
- To examine sex-dependent effects on astrocyte-microglial interactions after neonatal injury.
Main Methods:
- Utilized a hindpaw incision model in postnatal day 3 mice (both sexes).
- Performed 3D morphological analysis of individual astrocytes.
- Conducted transcriptomic analysis of spinal astrocytes at different postnatal ages.
- Observed microglial engulfment of astrocyte material.
Main Results:
- Neonatal incision caused age-dependent changes in astrocyte morphology: increased size/complexity at P4, reduced size/ramification at P10 and P24.
- Identified 76 differentially expressed genes at P4, related to cell motility and cytoskeleton, with fewer changes at later time points.
- Observed altered microglial engulfment of astrocyte material in a sex-dependent manner.
Conclusions:
- Neonatal injury significantly alters the postnatal development and maturation of spinal astrocytes in the SDH.
- These changes in astrocyte structure and gene expression may contribute to aberrant pain signaling.
- Early life injury impacts astrocyte-microglial interactions with sex-specific differences, highlighting a novel aspect of neurodevelopmental response to pain.
