Mechanisms of Endothelial Protection by Natural Bioactive Compounds from Fruit and Vegetables

ABSTRACT The endothelium is fundamental for the regulation of vascular tone and structure. Under disease conditions, including the presence of cardiovascular disease risk factors, the endothelium loses its protective role and becomes a proatherosclerotic structure. In this article we searched for strategies from PUBMED and Science Direct databases using the following key words: endothelium, natural bioactive compounds, polyphenols and cardiovascular diseases. The search was restricted to english language papers. Studies have identified the contribution of diet to the risk of developing cardiovascular diseases. In this context, high intakes of fruit and vegetables are associated with the decrease of cardiovascular diseases. Thus the most important fruit/vegetables and bioactive compounds to prevent endothelial diseases are berries, apples, virgin olive oil, tomatoes, soybeans, and polyphenols, carotenoids and unsaturated fatty acids, respectively. The bioactive compounds from fruit and vegetables provide endothelial protection through the following mechanisms: improved eNOS/NO bioavailability, attenuates oxidative stress, inhibited NF-κB pathway and decreased cell adhesion molecules expression. In this article natural bioactive compound mechanisms of endothelium protection are thoroughly reviewed.

High temperature and UV-C treatments affect stilbenoid accumulation and related gene expression levels in Gnetum parvifolium

Background: Gnetum parvifolium stems and roots have been used for a long time in traditional Chinese medicines. Stilbenes are bioactive compounds present in G. parvifolium plants, and they possess antioxidative and anticancer properties. However, little is known about the responses of G. parvifolium stilbene biosynthetic pathways to stress conditions. Therefore, we investigated stilbene biosynthesis, including the expression of relevant genes, in G. parvifolium exposed to high-temperature and ultraviolet-C treatments. Results: High temperatures did not influence the accumulation of total stilbenes in stems but decreased stilbene concentrations in roots at 3 h, with a subsequent restoration to control levels. In contrast, ultraviolet irradiation induced the accumulation of total stilbenes in stems but not in roots. We also observed that high temperatures inhibited the production of resveratrol and piceatannol in G. parvifolium stems and roots, whereas ultraviolet treatments initially inhibited their accumulation (up to 6 h) but induced their production at later time points. Analyses of specific genes (i.e., PAL, C4H, 4CL, STS, and CYP) revealed that their expression levels generally increased in stress-treated stems and roots, although there was some variability in the expression profiles during treatments. Conclusions: Our results indicated that high temperatures and ultraviolet irradiation differentially affect the biosynthesis of specific stilbenes in G. parvifolium stems and roots. Therefore, cultivating G. parvifolium seedlings under optimal stress conditions may increase the biosynthesis of specific stilbene compounds.