AB037. Icariside II improves human cavernous endothelial cells function by regulating miR-155/eNOS signal pathway

Background: To investigate the changes of miR-155/endothelial nitric oxide synthase (eNOS) signal pathway under the stimulation of age-BSA and glucose with or without icariside II (ICAII) intervention inhuman cavernous endothelial cells (HCECs).

Methods: Purified HCECs were first divided into three groups randomly: normal group + BSA (NC group), age-BSA + glucose group (DM group), ICAII treatment group (DM + ICAII group with different concentrations at 0.1, 1, 10 µM). Western Blot to detect the protein expression of eNOS and RAGE; real time PCR to detect the expression of miR-155 and eNOS; DAF-FM DA fluorescent probes assay and NaNO₃/NaNO₂ assay to detect the NO concentration. Lentivirus mediated miR-155 over-expression was constructed to observe the changes of eNOS and NO.

Results: The eNOS and RAGE expression in DM group is significantly reduced and increased respectively compared with that of NC group (P<0.05), while ICAII intervention could reverse this change effectively. The 10 µM of ICAII has the most powerful effect. MiR-155 has the highest fold changes among candidate miRNAs in diabetic like HCECs (P<0.05). MiR-155 increased and eNOS decreased remarkably in DM group, while ICAII intervention could inhibit the miR-155 expression, which led to the significantly higher eNOS expression and NO concentration (P<0.05). In lentivirus mediated miR-155 overexpression with or without ICAII intervention model, we found the similar trend with the above diabetic model.

Conclusions: MiR-155/eNOS signal pathway may be involved in the process of diabetic HCECs dysfunction. ICAII could promote the recovery of the endothelial dysfunction by regulating the miR-155/eNOS signal pathway.

Keywords: Erectile dysfunction; icariside II (ICAII); miR-155; nitric oxide synthase (NOS); endothelial dysfunction