Endocrine Abstracts

JOINT2291

Background: A common phenomenon observed in type 2 diabetes mellitus is the postprandial dysmetabolism, which may act as a daily stressor of the already dysfunctional diabetic platelets.

Methods: Ex-vivo experiments have been performed on isolated platelet-rich plasma of 16 healthy volunteers. Antiplatelet activity, of 7 most common bioactive phenolic compounds of olive oil, was assessed in isolated platelet-rich plasma (PRP) by optical transmittance aggregometry, using ADP and TRAP as aggregating factors. According to the ex-vivo results, the clinical study followed and had a randomized, crossover design. Ten T2DM patients consumed five isocaloric meals containing 120g white bread combined with: (i)39g butter, (ii)39g butter and 400mg ibuprofen, (iii)40mL OO (phenolic content<10mg/Kg), (iv)40mL OO with 250mg/Kg oleocanthal and (v)40mL OO with 500mg/Kg oleocanthal. Glycemia markers and lipid profile was measured in serum pre and postprandially, while the ex-vivo ADP- and TRAP-induced platelet aggregation were also calculated. TBARS and GPX3 were measured in plasma and TBARS and GPX1 in red blood cells(RBC), protein carbonyls(PC) in plasma pre- and post-prandially.

Results: Ex-vivo experiments showed that oleocanthal had better antiplatelet activity(APA) against ADP compared to TRAP while oleacein had milder APA than oleocanthal for all active agents. Regarding the clinical study, the glycemic and lipidemic response was similar between meals. However, a sustained (90-240 min) dose-dependent reduction in platelets’ sensitivity to both ADP (50–100%) and TRAP (20–50%) was observed after the oleocanthal meals. in comparison to other meals. The APA of the OO containing 500mg/Kg oleocanthal was comparable to that of the ibuprofen meal. OO meals induced an increase of TBARS measured in both plasma and RBC. The Incremental area under the curve (iAUC) of TBARS in plasma was lower in oleocanthal enriched OO compared to OO. The kinetic activity of GPX3 after BU-IBU consumption was similar with that of OO meals, while the iAUCs of OO meals were greater compared to BU. Regarding GPX1, the kinetic activity was similar after all meals, showing a postprandial increase till t=120min. The correlation analysis showed that the iAUC of the EC50 for ADP had an inverse correlation with iAUC of TBARS (r-=-0.311, P = 0.036). Moreover, positive was the correlation between iAUC of TBARS and iAUC of PC (r = 0.385, P = 0.008) while negative was the correlation between iAUC of RBC TBARS and LDL (r-=-0.348, P = 0.019).

Conclusions: The consumption of meals containing oleocanthal-rich OO can reduce platelet activity and has antioxidant properties, during the postprandial period, irrespective of postprandial hyperglycemia and lipidemia.