Researchers at the University of São Paulo showed, through animal models, that brain insulin resistance can drive both Alzheimer’s disease (AD)–like changes and seizure susceptibility, suggesting a mechanistic link between the two conditions. When rodents were given intracerebral streptozotocin to model “type 3 diabetes,” they developed memory deficits and displayed seizure-like responses to loud sound, along with AD-related molecular changes (eg, hippocampal tau hyperphosphorylation and reduced insulin receptors). Conversely, Wistar Audiogenic Rats bred for epilepsy exhibited AD-like molecular signatures, indicating the relationship may be bidirectional.
The findings bolster clinical observations that epilepsy increases later AD risk and that seizures are not uncommon in AD, while underscoring AD’s complexity beyond single-pathway (eg, amyloid) models. The team’s epilepsy-AD rat line has been deposited at the University of Missouri’s Rat, Resource, and Research Center. Follow-up research will analyze surgical epilepsy tissues and apply proteomic/transcriptomic profiling (in collaboration with Harvard) to validate human relevance. Together, the data argue for broader therapeutic strategies that target central insulin signaling to potentially mitigate both neurodegeneration and epileptogenesis.
Reference: São Paulo Research Foundation (FAPESP). Insulin resistance in the brain may link Alzheimer’s and epilepsy. News Medical. Published May 22, 2025. Accessed September 16, 2025. https://www.news-medical.net/news/20250522/Insulin-resistance-in-the-brain-may-link-Alzheimere28099s-and-epilepsy.aspx
