PROJECT SUMMARY Alzheimer’s disease (AD) is a devastating neurodegenerative disease is characterized by accumulation of amyloid-β (Aβ) and tau proteins, neuroinflammation, neuronal loss, and dementia. Currently, there are no disease-altering therapies for AD. Microglia, the immune cells of the brain, represent promising cellular targets for therapeutic development to modify the course of AD progression. Microglia transition to a unique state called disease associated microglia (DAM) in AD which contribute to AD pathogenesis via both protective and detrimental responses. A subset of DAM, known as proinflammatory DAM, promote neuronal injury and fail to phagocytize Aβ effectively. Preliminary studies indicate proinflammatory DAM undergo a bioenergetic shift toward a glycolytic state to sustain their detrimental responses. Therefore, identifying the regulators of the glycolytic shift is critical in determining novel avenues to inhibit proinflammatory responses in AD. Our lab found proinflammatory DAM highly express a potassium channel called Kv1.3, which regulates potassium efflux and cellular functions. Our lab’s work showed blockade of Kv1.3 channels in mouse models of AD pathology reduces neuroinflammation and Aβ pathology, but how Kv1.3 regulates the proinflammatory response in DAM remains unclear. I propose that Kv1.3 regulates inflammatory responses by controlling the bioenergetics of microglia. My central hypothesis is the Kv1.3 channel is a critical regulator of the bioenergetic switch and proinflammatory responses of microglia in AD pathology. I will use in vitro and in vivo approaches to examine how Kv1.3 modulates the bioenergetics and inflammatory responses of DAM. The long-term goal of this project is to examine the role of Kv1.3 in microglial bioenergetics and inflammation. In Aim 1, I will use an in vitro system to examine how Kv1.3 alters the microglial bioenergetics and immune function of microglia which will be activated by Aβ. Aim 1 will use seahorse assays, live cell imaging, immune profiling, and flow cytometry to describe these changes in bioenergetics and inflammatory response. In Aim 2, I will utilize a novel genetic approach to delete Kv1.3 selectively in microglia in vivo in an AD mouse model. This will allow me to measure the effects of Kv1.3 deletion in microglia on microglial bioenergetics and inflammatory responses via immune profiling, western blots, assays for key metabolites, and immunohistochemistry. These two parallel aims will allow me to elucidate a mechanism by which Kv1.3 regulates proinflammatory DAM responses in AD. By understanding Kv1.3 influence of microglia in AD, I will contribute to the understanding of biology behind AD and establish a potential therapeutic marker. Through the training I will gain in this proposal, I will be well prepared for my future career goal of becoming an independent investigator.