Journal of Visualized Experiments, cilt.2025, sa.221, 2025 (SCI-Expanded, Scopus)
Hypoxia can occur to varying degrees for different reasons during the perinatal period, affecting development. We aim to examine the consequences of mild to severe neonatal hypoxia in mice, focusing on its potential link to neurodegenerative fetal brain dysfunctions related to autism spectrum disorder (ASD). We induced hypoxia in neonatal mice by delivering them in controlled environments with varying oxygen concentrations. The results showed elevated levels of HIF-1α (a marker of hypoxia) in the cerebral cortex and hippocampus, as well as increased neurodegeneration in these regions. Moreover, we observed altered expression of ASD-related miRNAs (miR-19a-3p, miR-361-5p, miR-150-5p, miR-126-3p, and miR-499a-5p) in hypoxic groups, consistent with previous results in human and animal models of ASD. These molecular alterations were accompanied by behavioral changes such as decreased movement, speed, social interaction, and repetitive behaviors, as well as an increased tendency to exhibit corner-seeking behavior in mice subjected to hypoxic conditions. Although behavioral and molecular changes were detectable in the 12% O2 group (mild hypoxia), the most pronounced changes were observed in the more severe hypoxia groups, at 10% O2 and 8% O2. Overall, the results suggest that neonatal hypoxia can induce lasting molecular changes associated with neurodegenerative diseases with behavioral consequences. Moreover, even in normal birth, exposure to hypoxia during early development can impair memory and learning. The results highlight the need for early detection and intervention in newborns exposed to hypoxia to prevent long-term neurological problems. miRNA levels are regulated during development, and their modifications in tissues, especially in germ cells, constitute a risk factor for the next generation. The analyses provide a basis for studying the regulatory pathways that affect functional and behavioral changes under hypoxia.