The Olive Polyphenol Hydroxytyrosol Enhances Autophagy and Heme Oxygenase-1 Expression in Aortic Endothelial Cells and Reduces Arterial Stiffness ex vivo.

Age-related arterial stiffening is a hallmark of vascular ageing and a key driver of cardiovascular disease. Oxidative stress, impaired autophagy, and extracellular matrix remodelling play an important role in the progression of aortic stiffening. Hydroxytyrosol (HT), a phenolic compound in olives, has demonstrated antioxidant properties and the ability to modulate autophagy, positioning it as a potential therapeutic for vascular ageing.

Comparison of In Vitro Biotransformation of Olive Polyphenols Between Healthy Young and Elderly.

Background: Olive leaves are a rich source of polyphenols, predominantly secoiridoids, flavonoids, and simple phenols, which exhibit various biological properties. Extracts prepared from olive leaves are associated with hypoglycemic, hypotensive, diuretic, and antiseptic properties. Upon ingestion, a substantial fraction of these polyphenols reaches the colon where they undergo extensive metabolism by the gut microbiota.

Validation and optimisation of reduced glutathione quantification in erythrocytes by means of a coulometric high-performance liquid chromatography analytical method.

Glutathione (GSH), a tripeptide that consists of cysteine, glutamate and glycine, is present in all mammalian tissues in the millimolar range. Besides having numerous cellular functions, GSH is an important antioxidant and is considered a valuable biomarker in evaluating oxidative stress. This paper provides a sensitive analytical method using HPLC-ECD to quantify GSH in erythrocytes, validated using the ICH guidelines for Bioanalytical Method Validation.

Availability and Metabolic Fate of Olive Phenolic Alcohols Hydroxytyrosol and Tyrosol in the Human GI Tract Simulated by the GIDM-Colon Model.

Hydroxytyrosol (HTyr) and tyrosol (Tyr) are the most well studied phenolic alcohols of olive oil and olive products demonstrating numerous and significant beneficial health effects. However, their activity in the human organism as food bioactives is strongly associated with their bioavailability and metabolism, while manifested through their metabolites. Nevertheless, there are limited studies investigating their biotransformation and mainly catabolism by gut microflora under a holistic interpretation close to the human organism.