Infantile spasms is an age-specific
epileptic syndrome associated with poor developmental outcomes and poor response to nearly all traditional
antiepileptic drugs except
adrenocorticotropic hormone (
ACTH). We investigated the protective mechanism of
ACTH against brain damage. An
infantile spasm rat model induced by
N-methyl-D-aspartate (
NMDA) in neonate rats was used. Pregnant rats were randomly divided into the stress-exposed and the non-stress exposed groups, and their offspring were randomly divided into
ACTH-treated
spasm model, untreated
spasm model, and control groups. A proteomics-based approach was used to detect the
proteome differences between
ACTH-treated and untreated groups. Gel image analysis was followed by matrix-assisted
laser desorption/ionization time-of-flight mass spectrometric
protein identification and bioinformatics analysis. Prenatal stress exposure resulted in more severe
seizures, and
ACTH treatment reduced and delayed the onset of
seizures. The most significantly up-regulated
proteins included
isoform 1 of
tubulin β-5 chain, cofilin-1 (CFL1),
synaptosomal-associated protein 25,
malate dehydrogenase,
N(G),N(G)-dimethylarginine dimethylaminohydrolase 1,
annexin A3 (ANXA3), and
rho GDP-dissociation inhibitor 1 (ARHGDIA). In contrast,
tubulin α-1A chain was down-regulated. Three of the identified
proteins, ARHGDIA, ANXA3, and CFL1, were validated using western blot analysis. ARHGDIA expression was assayed in the brain samples of five
infantile spasm patients. These
proteins are involved in the cytoskeleton, synapses, energy metabolism, vascular regulation, signal transduction, and acetylation. The mechanism underlying the effects of
ACTH involves the molecular events affected by these
proteins, and
protein acetylation is the mechanism of action of the drug treatment.