In hyperglycemia and DKD conditions, the continual increase in UDP-GlcNAc inhibits GFAT expression via a negative feedback mechanism, resulting in a decrease in UDP-GlcNAc levels, inhibiting SP1 modification with O-GlcNAc and, therefore, downregulating ENTPD5 expression. Here, ENTPD5 is linked to Hyperglycemia.