OGA and liver dysplastic nodule: When we assessed the overall levels of O-GlcNAcylation, OGT, and OGA in human DN samples using Western blot, our results showed a significant reduction in total O-GlcNAcylation and OGT levels, an increase in OGA levels, as well as decreased MC proliferation and mesangial matrix accumulation, indicating that Metformin treatment not only affects the expression of OGT and OGA but also has a substantial impact on the overall O-GlcNAc modification status in DN samples (Fig. 1, K–P).