Diabetes versus Cognitive Decline: Exploring Biophysical Changes in the Hippocampus

Neurodegenerative diseases are progressive nervous system disorders that affect specific neuronal populations' function and maintenance. In 2020, it was estimated that 47 million people around the world were living with dementia, making it one of the main causes of dependence and disability. On the other hand, Diabetes mellitus is a chronic metabolic disease physiologically characterized by high blood glucose levels, mainly caused by insufficient insulin production or the body's lack of insulin response. Around 422 million people worldwide have Diabetes, the majority living in low- and middle-income countries, and 1.5 million deaths are directly attributed to Diabetes each year. Some patients with Diabetes are more prone to dementia than healthy people, especially those with Alzheimer's disease. Currently, the scientific community discusses that Alzheimer's disease may represent a specific form of Diabetes in the brain, which would be called Type 3 Diabetes Mellitus. To this end, in this study, we use Atomic Force Microscopy and Raman Spectroscopy as tools for analyzing vibrational and ultrastructural properties, such as topography, roughness, area, and volume, in addition to studying biophysical properties, such as adhesion and Young's modulus, of tissue from a control animal with type I and type II diabetes mellitus. This work shows an innovative approach from a biophysical point of view, enabling pertinent contributions in an area that still lacks studies, using techniques essential for neurodegenerative disease research.