SPP1 and type 2 diabetes mellitus: The synthetic phenotype has a strong ability to synthesize extracellular matrix, manifesting as excessive proliferation and fibrosis of smooth muscle cells, which can cause contractile dysfunction..Our study found that type 2 diabetes mellitus leads to a significant reduction of α-SMA and a significant increase of OPN in corpus cavernosum smooth muscle cells, which is consistent with the transformation of corpus cavernosum smooth muscle cells into synthetic cells, which may be the mechanism of type 2 diabetes mellitus leading to ED.