Reduced Circulating Endothelial Progenitor Cells and Downregulated GTCPH I Pathway Related to Endothelial Dysfunction in Premenopausal Women with Isolated Impaired Glucose Tolerance

Figure 4

The CTCPH I/BH4 pathway and the Tie2/Akt/eNOS signaling pathway of circulating EPCs in the three groups. Both GTCPH I expression (a) and intracellular BH4 (b) levels were lower in premenopausal women with i-IGT than that in NGT and IFG women (all ). No difference of the two indexes was observed between NGT and i-IFG women. Either the phosphorylation forms or the total protein of tie2 (c), Akt (d), and eNOS (e) of circulating EPCs had not exhibited significant difference between each two groups. Data are given as mean ± SD ( vs. NGT; vs. IFG, n = 20 for the NGT group and i-IGT group and n = 21 for IFG group). NGT: normal glucose tolerance; i-IFG: isolated impaired fasting glucose; i-IGT: isolated impaired glucose tolerance; GTPCH: guanosine triphosphate cyclohydrolase; BH4: tetrahydrobiopterin; Tie2: tyrosine kinase with immunoglobulin and epidermal growth factor homology domain-2; Akt: protein kinase B; eNOS: endothelial nitric oxide synthase.

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