Microencapsulated Pomegranate Reverts High-Density Lipoprotein (HDL)-Induced Endothelial Dysfunction and Reduces Postprandial Triglyceridemia in Women with Acute Coronary Syndrome

Abstract

(1) Background: the composition of high-density lipoproteins (HDL) becomes altered during the postprandial state, probably affecting their functionality vis-à-vis the endothelium. Since acute coronary syndrome (ACS) in women is frequently associated with endothelial dysfunction, it is likely that HDL are unable to improve artery vasodilation in these patients. Therefore, we characterized HDL from women with ACS in fasting and postprandial conditions. We also determined whether microencapsulated pomegranate (MiPo) reverts the HDL abnormalities, since previous studies have suggested that this fruit improves HDL functionality. (2) Methods: Eleven women with a history of ACS were supplemented daily with 20 g of MiPo, for 30 days. Plasma samples were obtained during fasting and at different times, after a lipid load test to determine the lipid profile and paraoxonase–1 (PON1) activity. HDL were isolated by sequential ultracentrifugation to determine their size distribution and to assess their effect on endothelial function, by using an in vitro model of rat aorta rings. (3) Results: MiPo improved the lipid profile and increased PON1 activity, as previously reported, with fresh pomegranate juice. After supplementation with MiPo, the incremental area under the curve of triglycerides decreased to half of the initial values. The HDL distribution shifted from large HDL to intermediate and small-size particles during the postprandial period in the basal conditions, whereas such a shift was no longer observed after MiPo supplementation. Consistently, HDL isolated from postprandial plasma samples hindered the vasodilation of aorta rings, and this endothelial dysfunction was reverted after MiPo consumption. (4) Conclusions: MiPo exhibited the same beneficial effects on the lipid profile and PON1 activity as the previously reported fresh pomegranate. In addition, MiPo supplementation reverted the negative effects of HDL on endothelial function generated during the postprandial period in women with ACS.

Microencapsulated Pomegranate Modifies the Composition and Function of High-Density Lipoproteins (HDL) in New Zealand Rabbits

“…These changes could be related to an improvement in the HDL functionality, i.e., increased PON1 activity, increased resistance for formation to Cu 2+ -induced conjugated lipid hydroperoxides, and the lack of an inhibitory effect on vasodilation dependent on the endothelium after supplementation with MiPo. These results agree with those reported in women with acute coronary syndrome after MiPo consumption [ 21 ]; however, in the present study we demonstrated the HDL modifications in an animal model characterized by very mild postprandial increases of plasma triglycerides, indicating that pomegranate has a beneficial effect on HDL functionality, independently of an improvement of the postprandial triglyceridemia. Moreover, the modifications of the lipid profile after MiPo in this study were similar that those observed in human.…”

“…The co-incubation of HDL isolated from plasma in fasting conditions, after supplementation with MiPo, induced an improvement in endothelial function using a model of aorta rings. Accordingly, Estrada et al [ 21 ] showed that MiPo supplementation after 30 days reversed the negative effects on endothelial function of HDL generated during the postprandial period in women with ACS. Therefore, the modifications of HDL structure and the enhancement of their antioxidant properties may explain the beneficial effects vis-à-vis the endothelial function [ 51 ].…”

“…The MiPo was prepared as previously described by Estrada et al [ 21 ]. A previous study reported that the MiPo has the same beneficial effects on lipid profile and PON1 activity as the fresh juice [ 20 ].…”

“…In this context, pomegranate is a source of flavonoids and phenolic compounds, among others, with hypolipemiant and antioxidant potential; in vivo and in vitro studies demonstrated that pomegranate alters HDL lipid composition and functionality [ 19 , 20 ]. Similarly, a previous study from our group demonstrated that after supplementation with microencapsulated pomegranate (MiPo) in women with acute coronary syndrome (ACS), postprandial triglyceridemia significantly decreased [ 21 ]. In that study, isolated HDL partially inhibited the endothelial-dependent vasodilation in vitro, and such effect was exacerbated during the postprandial state.…”

“…In that study, isolated HDL partially inhibited the endothelial-dependent vasodilation in vitro, and such effect was exacerbated during the postprandial state. Interestingly, the harmful effects of HDL on endothelial function were reverted after supplementation with MiPo and a concomitant increase of PON1 activity [ 21 ]. However, it remains unclear whether the pomegranate exerts an indirect beneficial effect on HDL through the improvement of the postprandial triglyceridemia or a direct effect that enhances HDL functionality.…”