Metformin administration restored GRP78 protein level to control value and elevated by 1.97 times compared with T2DM (p = 0.048) at the background of slightly declined Grp78 mRNA (by 1.56-fold, p = 0.05 vs. control and by 1.72-fold, p = 0.04 vs. T2DM). The gene discussed is HSPA5; the disease is type 2 diabetes mellitus.