The dipeptidyl peptidase-4 inhibitor, linagliptin, improves cognitive impairment in streptozotocin-induced diabetic mice by inhibiting oxidative stress and microglial activation

Makoto Ide, Noriyuki Sonoda, Tomoaki Inoue, Shinichiro Kimura, Yohei Minami, Hiroaki Makimura, Eiichi Hayashida, Fuminori Hyodo, Mayumi Yamato, Ryoichi Takayanagi, Toyoshi Inoguchi, Michael Bader
2020 PLoS ONE  
Accumulating epidemiological studies have demonstrated that diabetes is an important risk factor for dementia. However, the underlying pathological and molecular mechanisms, and effective treatment, have not been fully elucidated. Herein, we investigated the effect of the dipeptidyl peptidase-4 (DPP-4) inhibitor, linagliptin, on diabetes-related cognitive impairment. Streptozotocin (STZ)-induced diabetic mice were treated with linagliptin (3 mg/kg/24 h) for 17 weeks. The radial arm water maze
more » ... st was performed, followed by evaluation of oxidative stress using DNP-MRI and the expression of NAD(P)H oxidase components and proinflammatory cytokines and of microglial activity. Administration of linagliptin did not affect the plasma glucose and body weight of diabetic mice; however, it improved cognitive impairment. Additionally, linagliptin reduced oxidative stress and the mRNA expression of NAD(P)H oxidase component and TNF-α, and the number and body area of microglia, all of which were significantly increased in diabetic mice. Linagliptin may have a beneficial effect on diabetes-related dementia by inhibiting oxidative stress and microglial activation, independently of glucose-lowering.
doi:10.1371/journal.pone.0228750 pmid:32032367 fatcat:no7hjwdygff6dctyxbx25ywria