Aim: The aim of the present study was to evaluate the improvement of diabetic microangiopathy in patients suffering from this condition since at least five years, and whose disease was managed without insulin.
Methods: Curcumin, the orange pigment of turmeric, has recently received increasing attention because of its antioxidant properties, mediated by both direct oxygen radical quenching and by induction of anti-oxidant responses via Nrf2 activation. This aspect, combined with the beneficial effects on endothelial function and on tissue and plasma inflammatory status, makes curcumin potentially useful for the management of diabetic microangiopathy. To further evaluate this, Meriva, a lecithinized formulation of curcumin, was administered at the dosage of two tablets/day (1 g Meriva/day) to 25 diabetic patients for four weeks. A comparable group of subjects followed the best possible management for this type of patients.
Results: All subjects in the treatment and control group completed the follow-up period; there were no dropouts. In the treatment group, at four weeks, microcirculatory and clinical evaluations indicated a decrease in skin flux (P<0.05) at the surface of the foot, a finding diagnostic of an improvement in microangiopathy, the flux being generally increased in patients affected by diabetic microangiopathy. Also, a significant decrease in the edema score (P<0.05) and a corresponding improvement in the venoarteriolar response (P<0.05) were observed. The PO2 increased at four weeks (P<0.05), as expected from a better oxygen diffusion into the skin due to the decreased edema. These findings were present in all subjects using Meriva, while no clinical or microcirculatory effects were observed in the control group.
Conclusion: Meriva was, in general, well tolerated, and these preliminary findings suggest the usefulness of this curcumin formulation for the management of diabetic microangiopathy, opening a window of opportunities to be evaluated in more prolonged and larger studies. The molecular mechanisms involved in the beneficial effects of curcumin on microcirculation and edema are also worth investigation.