Aim: Aim of the study was to investigate plasma levels of intercellular adhesion molecule-1 (s-ICAM-1) and vascular cellular adhesion molecule-1 (s-VCAM-1) in a cohort of type 2 diabetic patients, compared to healthy control subjects, to verify whether there are differences between these two molecules and to evaluate a possible correlation with the presence of microangiopathy.
Methods: Plasma ICAM-1 and VCAM-1 levels in 49 type 2 diabetic patients, 28 microalbuminuria patients and 21 normoalbuminuria patients were investigated and compared to same levels of 15 healthy control subjects. ICAM-1 and VCAM-1 were assayed by EIA commercial kit (R&D System Co, Abington, UK), according to procedures described by the manufacturer and concentrations expressed as ng/mL. Mean +/- standard deviation (SD) values for each group were compared by t test for unpaired data and Kruskall-Wallis test. Statistical significance was set at P<0.05.
Results: Mean +/- SD plasma ICAM-1 was 12.96 +/- 1.08 ng/mL in controls, 18.56 +/- 2.3 ng/mL in normoalbuminuria patients and 26.25 +/- 4.1 ng/mL in microalbuminuria patients, respectively. Mean +/- SD plasma VCAM-1 was 15.96 +/- 4.02 ng/mL in controls, 17.13 +/- 7.5 ng/mL in normoalbuminuria patients and 26.84 +/- 5.99 ng/mL in microalbuminuria patients, respectively. Statistical analysis showed a significant difference in ICAM-1 levels between controls and normoalbuminuria patients (P<0.05) and between these and microalbuminuria patients (P<0.05). VCAM-1 levels were significantly higher in microalbuminuria than in normoalbuminuria patients (P<0.05), but no significant difference was found between normoalbuminuria patients and control subjects (P>0.05).
Conclusion: Reported results show that circulating ICAM-1 is higher in microalbuminuria than in normoalbuminuria patients and also in normoalbuminuria patients than in control subjects. Circulating VCAM-1 has increased only in microalbuminuria patients. Therefore, these two molecules have different ability to assess temporal relationship between inflammatory activity and microvascular complications.