T09-P-03 Is endothelial apoptotic cell increment the major player in diabetic ED? An anatomoclinical study

Abstract

Objective Our previous studies with animal models suggested that loss of erectile tissue cell integrity may be a relevant mechanism involved in erectile dysfunction (ED). To evaluate this hypothesis, we characterized vascular and smooth muscle cell (SMC) structure and viability in human cavernosal fragments of normal potent and diabetic impotent individuals. We further compared these results to patient age, arterial risk factors, Penile Nitric Oxide release test (PNORT) response to intracavernous injections (ICI) of vaso-active medications. Design and Methods 13 erectile tissue samples were harvested from diabetic impotent patients and 5 normal non-diabetic potent controls. Evaluation of vascular and SMCs was performed by immunohistochemistry for von Willebrand Factor and ???-smooth muscle actin. Tissue integrity was assessed by TUNEL assay and an index of apoptotic cell density (ACD) defined (number of apoptotic cells/tissue area (mm 2 )). These results were compared to patient clinical data as aforementioned. Results Results showed that normal controls had a low ACD (7,15/mm 2 ), compared to diabetics, which presented a higher ACD (23,82/mm 2 ). Apoptotic cells in diabetics were located mainly in the cavernous endothelium and perivascular areas. Higher ACD correlated with low PNORT and ICI responses and with severe penile arterial disease. Increased age and number of arterial risk factors may play a role in decreasing endothelial function. Conclusions Apoptotic cells are increased in diabetic vascular and perivascular cavernosal tissue, demonstrating that apoptosis is one of the main mechanisms involved in endothelial dysfunction in diabetic-ED. PNORT appears to be a promising non invasive test to evaluate penile endothelial functioning.