GNAI1 and type 2 diabetes mellitus: In the hepatic membranes of db/db mice, the levels of expression of Gαi2, Gαi3, and Gβ subunits were reduced by 75%, 63%, and 73%, respectively, and the maximal inhibitory effect of GppNHp on forskolin-stimulated AC activity was reduced to 60%, as compared to lean animals, which indicates the abolition of Gi proteins activity in the liver in T2DM [149].