Transgelin (TAGLN) is elevated in endothelial colony-forming cells (ECFCs) from gestational diabetes mellitus (GDM) pregnancies. A: RNA was isolated from ECFCs obtained from uncomplicated (UC), GDM-conservatively managed (CM), and GDM-insulin (INS) controlled pregnancies. Using quantitative real-time polymerase chain reaction, relative amounts of TAGLN mRNA were quantified and normalized to hypoxanthine phosphoribosyltransferase (HPRT). Data were analyzed by one-way ANOVA followed by a Kruskal-Wallis post hoc test. ECFCs from GDM-INS pregnancies had significantly higher levels of TAGLN mRNA compared with samples from UC pregnancies (UC: n = 8; GDM-CM and GDM-INS: n = 4; *P = 0.046). B: representative Western blot is shown using whole cell lysates from UC, GDM-CM, and GDM-INS samples. The membrane was probed with antibodies against TAGLN and vinculin (VINC). Band intensity was quantified using ImageJ, and TAGLN protein levels were normalized using VINC. Data were analyzed by one-way ANOVA followed by a Kruskal-Wallis post hoc test. GDM-INS samples had increased TAGLN compared with UC controls (UC: n = 5; GDM-CM and GDM-INS: n = 3; *P = 0.019).