Altered expression of synaptic proteins and adhesion molecules in the hippocampus and cortex following the onset of diabetes in nonobese diabetic mice

Abstract

Mounting evidence links Type 1 diabetes (T1D) with cognitive dysfunction, psychiatric disorders, and synaptic alterations; however, the underlying mechanism remains unclear. Numerous synaptic proteins and synaptic adhesion molecules (SAMs) that orchestrate synaptic formation, restructuring, and elimination are essential for proper brain function. Currently, it is unclear whether the pathogenesis of T1D is related to the expression of synaptic proteins and SAMs. Here, we investigated whether T1D mice exhibited altered synaptic protein and SAM expression in the hippocampus and cortex. We discovered that T1D mice exhibited partially decreased levels of excitatory and inhibitory synapse proteins and SAMs, such as neurexins, neuroligins, and synaptic cell adhesion molecules. We also found that compared to control mice, T1D mice showed a marginal decrease in body weight and a significant increase in plasma glycoalbumin levels (a hyperglycemia marker). These results provide novel molecular-level insights into synaptic dysfunction in mice with T1D.