Effect of vildagliptin conjugated monometallic nanoparticles and bimetallic nanocomposites on diabetes-induced cognitive deficit

Oxidative stress is one of the major causes of different metabolic disorders, including diabetes, cardiovascular diseases, neurodegenerative diseases and cancers. Some metabolic disorders like diabetes mellitus leads to secondary complications after micro and macrovascular complications. Some of the most prevalent neurodegenerative diseases, like cognitive impairment and Alzheimer's disease, are found in chronic diabetic patients. The present study is designed to understand the mechanism of interconnection between diabetes mellitus and cognitive deficit using the alloxan model of diabetes-induced cognitive deficit in the rat model. The alloxan monohydrate produces reactive oxygen species, producing superoxide free radicals, hydrogen peroxide and hydroxyl radicals. The hydroxyl radicals ultimately cause the death of beta cells, causing diabetes. Hence, the correlation of oxidative stress and neurodegeneration in cognitive impairment is the trigger for this study. In the present study, we investigate the ameliorative effect of vildagliptin (VLD) and its conjugated nanoparticles against alloxan-associated brain damage due to oxidative stress. The gold (Au), selenium (Se) nanoparticles, and bimetallic (Se@Au) nanocomposites of VLD are synthesized and assessed for improvement in their brain availability. The in-vitro antioxidant evaluation of the VLD and nanoparticles is done using DPPH, ABTS, and FRAP assay. The memory-related neurobehavioral studies, in-vivo antioxidant studies, in-vivo biochemical studies, and histopathological examinations are evaluated in rat brains. The VLD and its nanoformulations exhibited in-vitro and in-vivo antioxidant properties significantly (p < 0.01). They reduced the activity of AChE and nitrite in the alloxan diabetic rats. The bimetallic Se@Au VLDNCs displayed a more protective effect than VLD, VLD-AuNPs, and VLD-SeNPs.