Real-time RT-PCR Ct values for blood GAPDH correlate with measures of vascular endothelial function in humans.

PURPOSE

To date, there is a wide range of methods in use to assess endothelial function, each with its own advantages and limitations. Here, we tested hypothesis that real-time RT-PCR threshold value (Ct), which is reflective of mRNA level, for Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) from whole blood is indicative of endothelial function in humans.

MATERIALS AND METHODS

To assess vascular function, we measured baseline skin perfusion, postocclusion reactive hyperemia (PORH), and brachial artery flow-mediated dilatation (FMD) and tested for a possible correlation between vascular responses and blood GAPDH real-time RT-PCR Ct value in 75 healthy volunteers.

RESULTS

Tests known to measure, at least in part, endothelial function such as baseline skin perfusion, the 2-minute recovery PORH, and FMD exhibited significant positive correlations with blood GAPDH Ct values. In contrast, there was no significant correlation between Ct values for blood GAPDH and peak PORH, an endothelium-independent parameter.

CONCLUSIONS

Based on these findings, we report that GAPDH mRNA level in the blood correlates with vascular function in healthy subjects. This suggests that GAPDH mRNA level could be a potential biomarker of vascular endothelial function.