Maternal Infection Impairs Motor Coordination in an Experimental Meningitis Rat Model Through Altered MMP-2/3/9 Activity, H3K4 Trimethylation, and Reln Methylation

Maternal infection (MI) can increase the risk of neurodevelopmental and behavioural changes. This study examined MI-induced changes in motor coordination through the inflammatory-pathway-mediated epigenetic status of Reln. On gestational day (GD) 10, rats were assigned as (i) Control (Ctrl); (ii) Cronobacter sakazakii (CS) infection on GD-10 through recto-vaginal colonization; (iii) Negative Control (NC) [infected with C. sakazakii and treated with dimethyl sulfoxide (DMSO) 1 h before and 24 h after infection]; and (iv) C. sakazakii-infected rats treated with matrix metalloproteinase inhibitor (MMPI), 1 h before and 24 h after infection (CS + MMPI). Offspring were subjected to footprint analysis and the ladder rung walking test, which revealed that MI caused significant deficits in motor coordination. In addition, MI activated complement components—a disintegrin and metalloproteinase with thrombospondin motifs-1 (ADAMTS-1, C5a)—as well as proinflammatory cytokines such as interleukin-6 (IL-6) and matrix metalloproteinases (MMP-2, MMP-3, and MMP-9). Furthermore, the levels of DNA methyltransferase 3 alpha (DNMT3A), methyl-CpG-binding protein 2 (MeCP2), and histone H3 lysine 4 trimethylation (H3K4me3) were elevated in the CS and NC groups. Concurrently, the level of Reln promoter methylation increased; as a result, mRNA and protein, as well as postsynaptic density protein-95 (PSD-95), levels were decreased. Overall, the findings suggest that MI altered MMP-2/3/9 activity, H3K4me3, and the methylation of Reln, thereby affecting reelin, synaptic protein expression, and motor coordination in an experimental meningitis rat model.