Animal models of infantile spasms: Focus on new treatments

Infantile spasms (IS) represent a severe encephalopathy of infancy, which is a result of multiple etiologies. IS are characterized by intractable spastic seizures, EEG hypsarrhythmia, and cognitive decline. First-line treatments for IS include ACTH, corticosteroids, and vigabatrin. Our model combines prenatal exposure to betamethasone leading to HPA axis alterations and postnatal trigger of developmentally specific spasms using NMDA. The model is validated as it is etiologically relevant and resembles the semiology of the human IS, and it is sensitive to ACTH, corticoids as well as vigabatrin (representing construct, face, and predictive validity). Thus, the model offers a useful tool to study underlying mechanisms of IS, mechanisms of action of IS medications, and allows to test novel treatments, especially for the cryptogenic type of IS. The model is used by numerous investigators worldwide. Several other models of IS have been developed in recent years based on the various etiologies. The use of these models is more limited as they lack strict validation. Several new treatments have been tested using our model; however, the best efficacy was found only in those treatments biochemically related to currently used hormones. New approaches for treatment of IS are still needed.