Tea polyphenol ameliorates memory impairment in aged type 2 diabetic rats by modulating hippocampal glucose uptake/metabolism and O-GlcNAc glycosylation/phosphorylation of Tau

Abstract

Diabetes mellitus (DM) plays a causative role in memory impairment. Neuroprotective effects of tea polyphenol (TP), a unique and vital functional component of tea, have been widely investigated in neurodegenerative diseases, but the exact mechanisms have still not been entirely clarified yet. Here, we conducted the experiment to assess whether TP could protect the aged T2DM rats from memory impairment and its potential mechanisms. Our study revealed that memory impairment in aged T2DM rats was alleviated after TP treatment. Both in vivo and in vitro experiments showed that TP raised expression of GLUT4, activities of key enzymes of glucose metabolism and production of ATP in the model group, along with elevated O-GlcNAc glycosylation and reduced phosphorylation of Tau. Collectively, TP ameliorates memory impairment in aged T2DM rats via modulating hippocampal glucose uptake/metabolism and O-GlcNAc glycosylation/phosphorylation of Tau, which provides new insights into the beneficial effect of TP on DM-related memory impairment.

Keywords

• Tea polyphenol
• Aged
• T2DM
• Memory impairment
• Glucose metabolism