Effect of γ-Aminobutyric Acid–Chitosan Nanoparticles on Glucose Homeostasis in Mice

Diabetes mellitus is the most common endocrine disease worldwide; hyperglycemia is a hallmark of this disease. To alleviate the pain caused by diabetes, developing and utilizing effective diabetic drugs to maintain or recover the function of the residual β-cells is an attractive therapeutic approach. γ-aminobutyric acid (GABA) has been shown to have such effects, but it is easy to have reduced GABA activity under physiological conditions. In the present study, GABA–chitosan nanoparticles (GABA–CS NPs) were prepared, and glucose homeostasis, pancreatic β-cell protection, and anti-inflammatory effects of GABA–CS NPs were investigated in vivo. The results showed that blood glucose levels and IL-1β levels in the GABA–CS NP-administered group were both significantly lower, whereas the PDX1 expression was significantly higher than that of the impaired group (p < 0.01). This indicates that GABA–CS NPs can efficiently maintain glucose homeostasis, protect β-cells, and inhibit inflammation. These nanoparticles have the potential to be applied for future diabetes theranostics.