This review article examines the development of small molecule analogs of angiotensin IV, particularly dihexa, as potential therapeutic agents for neurodegenerative diseases including Alzheimer’s and Parkinson’s disease, synthesizing evidence from preclinical research on mechanisms of neuroprotection and cognitive enhancement. The review discusses how these analogs may work through the AT4 receptor pathway to promote neuroplasticity and reduce neuroinflammation, drawing on findings from animal models and in vitro studies, though clinical evidence in human subjects remains limited.
**Evidence level:** Review article synthesizing animal model and in vitro research