EDN1 and diabetes mellitus: It was demonstrated that treatments with HT or polyphenol extract from EVOO reverted multiple changes induced by high glucose and free fatty acids (FFAs) (features found in diabetes patients) which included nitric oxide (NO) level reduction and increased endothelin-1 (ET-1) levels induced by acetylcholine by modulating intracellular Ca2+ levels and endothelial nitric oxide synthase phosphorylation.